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[CABOT MICROELECTRONICS LOGO]





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                            CODE OF BUSINESS CONDUCT






















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                               V.2 November, 2002


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           CABOT MICROELECTRONICS CORPORATION CODE OF BUSINESS CONDUCT

0.0  CABOT MICROELECTRONICS CORPORATION'S VISION AND VALUES

1.0  A LETTER FROM THE CHAIRMAN AND CHIEF EXECUTIVE OFFICER

2.0  INTRODUCTION

3.0  YOU AND YOUR JOB AT CABOT MICROELECTRONICS
     3.1  Communications Channels
     3.2  Personal Conduct
     3.3  Work Environment
     3.4  Employee Privacy
     3.5  Protecting CMC's Assets
          3.5.1  Physical Assets
          3.5.2  Financial Assets
          3.5.3  CMC Information and Communication Systems
          3.5.4  Proprietary Information
                 3.5.4.1  Inadvertent Disclosure
                 3.5.4.2  Direct Requests for Information and Contacts with the
                          Press, Analysts and Others
                 3.5.4.3  Using Proprietary Information
          3.5.5  CMC Intellectual Property Rights
          3.5.6  Leaving CMC
          3.5.7  Legal Remedies
     3.6  Recording and Reporting Information

4.0  DEALING WITH OTHERS OUTSIDE OF CABOT MICROELECTRONICS
     4.1  Bribes, Gifts and Entertainment
          4.1.1  Business Amenities
          4.1.2  Receiving Gifts
          4.1.3  Referral Fees
          4.1.4  Giving Gifts
          4.1.5  Relationships with Government Employees
          4.1.6  Public Official and Campaign Visits, Speaking Engagements and
                 Honoraria
     4.2  Complying with Laws
          4.2.1  Competition
          4.2.2  Export
          4.2.3  Antiboycott
          4.2.4  Import
          4.2.5  The Environment
          4.2.6  Lobbying
          4.2.7  Disclosure Obligations

5.0  FURTHER GUIDANCE REGARDING WORKING WITH CUSTOMERS, SUPPLIERS AND OTHER
     OUTSIDE PARTIES
     5.1  Avoiding Misrepresentation
     5.2  Dealing with Suppliers
          5.2.1  Avoiding Reciprocal Dealing
     5.3  Competing in the Field
          5.3.1  Working with Customers and Avoiding False and Misleading
                 Statements about Competitors
     5.4  Relationships with Other Organizations
          5.4.1  Complementary Third Parties
          5.4.2  Business Contacts with Competitors
          5.4.3  Prohibitions
     5.5  Acquiring and Using Information about Others
     5.6  Information Owned by Others
          5.6.1  Receiving Information that May Be Confidential or Have
                 Restrictions on Its Use
          5.6.2  Acquiring Software
     5.7  Using Trademarks




                               V.2 November, 2002
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6.0  YOUR OWN ACTIVITIES
     6.1  Conflicts of Interest
          6.1.1  Assisting a Competitor
          6.1.2  Competing against CMC
          6.1.3  Supplying CMC
          6.1.4  Personal Financial Interests
                 6.1.4.1  Publicly Traded Securities
                 6.1.4.2  Closely Held Organizations
     6.2  Using Inside Information and Insider Trading
     6.3  Using CMC's Time and Assets
     6.4  Public Service
     6.5  Participation in Political Life
          6.5.1  Speaking Out
     6.6  Someone Close to You Working in the Industry

7.0  SOME ADDITIONAL GUIDANCE

8.0  CODE OF BUSINESS CONDUCT CERTIFICATION












                               V.2 November, 2002
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0.0  CABOT MICROELECTRONICS CORPORATION'S VISION AND VALUES

VISION

     We are the company others pursue in technology and product performance. Our
     people and our business partners are our competitive advantage. We create
     value for our global customers and shareholders by unlocking the
     opportunity in unsolved problems.

VALUES

     Integrity
               -    We are honest and ethical in all of our dealings with all of
                    our employees, customers, business partners, suppliers,
                    competitors, and other stakeholders.
               -    We adhere to all laws, regulations, and our business
                    practices.
     Respect
               -    We value people's differences.
               -    We value diverse opinions, we listen and learn.
               -    We treat people fairly and respect their need for work/life
                    balance.
               -    We provide honest, constructive, and discreet feedback.
     Accountability
               -    We admit mistakes, we learn from our mistakes, we ask for
                    help.
               -    We take ownership and responsibility for our actions and
                    performance.
               -    We take initiative to make a difference and to help.
               -    We focus on results.
               -    We recognize and celebrate our successes.
     Competitiveness
               -    We are relentless in our pursuit of success.
               -    We are a leader in the markets we serve.
               -    We are committed to ensuring that we have the best people
                    and talent, technology, quality, service, and market
                    knowledge.
               -    We act with a sense of urgency, and we strive for excellence
                    in everything we do.
     Innovation
               -    We work creatively to develop new ways to provide value to
                    our customers.
               -    We drive our innovation by understanding stated and unstated
                    market needs, and we are the first to deliver against those
                    needs.
               -    We create new markets with unique technologies and
                    solutions.

1.0  A LETTER FROM THE CHAIRMAN AND CHIEF EXECUTIVE OFFICER

Dear Fellow CMC Employee:

     This Code of Business Conduct essentially is about Cabot Microelectronics'
     Vision and Values, which are the foundation of our company.

     Each employee has the responsibility to act according to our Vision and
     Values. CMC operates in one of the most competitive and fast-moving
     industries, and this environment emphasizes the importance of each
     employee's responsibility to exercise sound business judgment and act
     ethically. This Code of Business Conduct gives you the basic guidelines for
     understanding your responsibilities.

     While we each know that ethical behavior is important in its own right, it
     also is essential to our business success because it fosters our
     relationships with our customers, suppliers, communities in which we
     operate, and other stakeholders.

     We ask you to read our Code of Business Conduct, follow it, and continue to
     exhibit the Vision and Values and ethical conduct that has been a
     fundamental principle of our company since our beginning.

     Matthew Neville
     Chairman & Chief Executive Officer
     March 2002



                               V.2 November, 2002
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2.0  INTRODUCTION

At Cabot Microelectronics Corporation, the Chief Executive Officer and other
executive officers, along with CMC's Board of Directors, are responsible for
setting standards of business ethics and overseeing compliance with these
standards for CMC and its subsidiaries ("CMC"). It is the individual
responsibility of each employee (including directors and officers) of CMC and
its subsidiaries ("CMC employees") to comply with these standards.

As CMC employees, we frequently encounter a variety of ethical and legal
questions. We should decide these situations in ways that are consistent with
CMC's Vision and Values. CMC expects all employees to obey the law and to act
ethically. CMC's Code of Business Conduct provides general guidance for
resolving a variety of legal and ethical questions for CMC employees.

Because rapid changes in our business and industry present new ethical and legal
issues on an ongoing basis, no one set of guidelines should be considered the
definitive statement for all circumstances. If you have any questions about
interpreting or applying this Code of Business Conduct--or about guidelines and
procedures published by CMC or its subsidiaries or operating units --it is your
responsibility to consult your manager, the Human Resources Department or the
Office of the CMC General Counsel. A violation of any CMC guidelines or this
Code of Business Conduct can result in disciplinary action, including dismissal.

Each section of this Code of Business Conduct covers an area in which we have
responsibilities to CMC as employees:
          -    Personal conduct and protection of CMC's assets
          -    Obligations in conducting CMC's business with other people and
               organizations
          -    Conflicts of interest and other considerations affecting CMC
               that may arise from our own activities

Our responsibilities as CMC employees generally can be summarized as:
          -    Acting according to CMC's Vision and Values
          -    Acting honestly
          -    Treating others fairly
          -    Protecting CMC's physical and intellectual property
          -    Avoiding conflicts of interest
          -    Complying with laws

While CMC employees are expected to comply with all of the provisions of CMC's
Code of Business Conduct, certain sections of the Code will be more applicable
to certain of our employees, depending on their job responsibilities (for
example, Section 5 will be especially informative for those CMC employees whose
jobs involve working with our customers, suppliers or other outside
organizations, like research universities or laboratories).

3.0 YOU AND YOUR JOB AT CMC

3.1 Communications Channels

     If you know of an unlawful or unethical situation, you should immediately
     tell CMC whatever you know or have heard about it; you can do so in one of
     several ways. Contacting your manager is the best place to start, but you
     can also contact CMC's Human Resources Department, CMC counsel, including
     CMC's General Counsel, who has been designated CMC's Compliance Officer,
     CMC's Internal Audit Manager, or any other CMC manager. You may contact us
     in person, on the phone, through email, or in writing. In addition, you may
     call the CMC Ethics Line at 630/499-2702 (either direct or collect) or send
     an email to Ethics_Email@cabotcmp.com to report any concern you may have.
     You also may contact directly any member of our Board of Directors,
     including any member of our Board's Audit Committee. You may report your
     concern on an anonymous basis if you would like.

     CMC will promptly review your report of unlawful or unethical conduct, and
     CMC will not tolerate threats or acts of retaliation against you for
     notifying us of your concerns.




                               V.2 November, 2002
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3.2 Personal Conduct

     We should never take for granted CMC's reputation for integrity and
     business ethics - it's in each of our hands. To maintain that reputation,
     you must follow all of CMC's Code of Business Conduct and exercise good
     judgment in your decisions and actions.

     If CMC finds that your conduct on or off the job adversely affects your
     performance, that of other employees, or CMC's legitimate business
     interests, you can be subject to disciplinary measures, including
     dismissal.

3.3 Work Environment

     CMC strives to maintain a healthy, safe and productive work environment
     that is free from discrimination or harassment based on race, color,
     religion, sex, sexual orientation, age, national origin, disability, or
     other factors that are unrelated to CMC's legitimate business interests.
     CMC will not tolerate sexual advances, actions or comments or racial or
     religious slurs, jokes or any other comments or conduct in the workplace
     that creates, encourages or permits an offensive, intimidating or
     inappropriate work environment.

     If you believe that you are subject to such conduct, or have observed
     others subject to such conduct, you should tell CMC through any of the
     communication channels that you feel most comfortable in using - your
     manager, the Human Resources Department, CMC counsel, or any of the
     communications channels referenced above. Your complaint of such conduct
     will be reviewed promptly. Employees who are found to have engaged in
     harassment or discrimination, or to have misused their positions of
     authority in this regard, will be subject to disciplinary measures,
     including dismissal.

     Other conduct that is prohibited because of its adverse impact on the work
     environment includes: (1) threats; (2) violent behavior; (3) the possession
     of weapons of any type; (4) the use of recording devices, including
     videophones and Web cameras, for other than management approved purposes;
     and (5) the use, distribution, sale or possession of illegal drugs or any
     other controlled substance, except for approved medical purposes. In
     addition, employees should not be on CMC premises, in the CMC work
     environment or at CMC-sponsored events if they are under the influence of
     or affected by illegal drugs, controlled substances used for nonmedical
     purposes or alcoholic beverages. Consumption of alcoholic beverages on CMC
     premises is only permitted, with prior management approval, for
     company-sponsored events.

3.4 Employee Privacy

     CMC and CMC authorized companies and individuals collect and maintain
     personal information that relates to your employment, including
     compensation, medical and benefit information. Because CMC is a global
     organization with business processes, management structures and technical
     systems that cross country borders, you acknowledge that, to run its
     business, CMC and its authorized companies may transfer personal
     information about you as a CMC employee to any of the countries where we do
     business. While not all countries have a data protection law, CMC has
     world-wide policies that are intended to protect information wherever it is
     stored or processed. For example, access to your personal information is
     restricted to people with a need to know. Personal information is normally
     released to outside parties only with employee approval, except that CMC
     and authorized companies and individuals may also release personal
     information to verify employment, to satisfy the legitimate requirements of
     a company or other entity which is considering acquiring some of CMC's
     business operations, or for appropriate investigatory, business or legal
     reasons. Employees who have access to personal information must ensure that
     the information is not disclosed in violation of CMC's policies or
     practices.

     Personal items, messages or information that you consider personal or
     private should not be placed or kept anywhere in the CMC workplace, such as
     in telephone systems, office systems, electronic files, desks, credenzas,
     lockers, or offices. CMC's management has the right to access those areas
     and any other CMC furnished facilities. Additionally, in order to protect
     its employees and assets, CMC may ask to search an employee's personal
     property, including briefcases and bags, located on or being removed from
     CMC locations; the employee is expected to cooperate with such a request.
     Employees, however, should not access another employee's workspace,
     including electronic files, without prior approval from management.

3.5 Protecting CMC's Assets

     CMC has a large variety of assets. Many are of great value to CMC's
     competitiveness and success as a business. They include our physical assets
     and our extremely valuable proprietary information, such as CMC's
     intellectual property and CMC's confidential information.


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     Protecting all of these assets is critical. Their loss, theft or misuse
     jeopardizes the future of CMC.

     You are personally responsible for protecting CMC's property entrusted to
     you and for helping to protect the company's assets in general. To do this,
     you should be aware of and understand CMC's security and information
     protection procedures. You should be alert to any situations or incidents
     that could lead to the loss, misuse or theft of company assets and
     property. You should report all such situations to your manager or the
     Office of the General Counsel as soon as they come to your attention.

     Let's review the types of assets you should be concerned about protecting,
     and your related responsibilities.

     3.5.1 Physical Assets

          CMC's physical assets, such as equipment, systems, facilities,
          corporate charge cards and supplies, must be used only for conducting
          CMC's business or for purposes authorized by management.

     3.5.2 Financial Assets

          CMC's financial assets and funds must be used properly, accurately,
          and only for conducting CMC's business. No undisclosed or unrecorded
          fund or asset of CMC may be established for any purpose. No entity,
          fund or asset of CMC may be created or maintained for any purpose that
          is not properly reflected in CMC's books and records. No payment on
          behalf of CMC may be approved or made with the intention,
          understanding or awareness that any part of such payment is to be used
          for any purpose other than that described by the documents supporting
          the payment.

     3.5.3 CMC Information and Communication Systems

          CMC's information and communication systems, including CMC connections
          to the Internet, are vital to CMC's business; you should only use them
          for appropriate purposes. You can use them for conducting CMC business
          or for other incidental purposes authorized by your management or by
          applicable CMC guidelines, such as those on Internet use. For example,
          it is inappropriate to use CMC systems to visit Internet sites that
          feature sexual content or that advocate intolerance of others. It is
          also inappropriate to use them in a manner that interferes with your
          productivity or the productivity of others. You are responsible to
          ensure that your use of CMC systems is appropriate; inappropriate use
          of our systems is a misuse of CMC assets.

     3.5.4 Proprietary Information

          CMC proprietary information is any information that is owned by CMC,
          including information in CMC databases. Much, but not all, of CMC
          proprietary information is confidential. It may also be subject to
          copyright, patent or other intellectual property or legal rights.
          Proprietary information includes such things as: CMC's technical,
          manufacturing or scientific information relating to current and future
          products, offerings, and research; formulas and formulations; work
          instructions; business or marketing plans or projections; earnings and
          other financial data; personnel information including organizational
          changes; and software.

          CMC's proprietary information is the result of the ideas and hard work
          of many of your fellow employees and of substantial investments by CMC
          in planning, research and development. This information, particularly
          CMC confidential information, gives CMC a competitive advantage in the
          marketplace, and CMC would be damaged if its competitors learned of
          it.

          The value of CMC's proprietary information is well known not only to
          CMC's competitors but also to others in the industry, such as security
          analysts, members of the press, and consultants. CMC would be harmed
          by unauthorized disclosures of its proprietary information to, or the
          unauthorized use of that information by, any of those people. For
          example, unauthorized disclosure of an unannounced CMC product can
          hurt us by giving competitors more time to match our product. Or,
          unauthorized disclosure of financial information or issues with
          particular suppliers or customers, whether positive or negative, can
          impact our stock and our responsibilities with respect to securities
          laws. Another example is unauthorized disclosure of an unannounced
          organizational or personnel change that can adversely affect employee
          morale and can interfere with our plans.

          As a CMC employee, you will have access to information that CMC
          considers proprietary. Given outside interest in CMC and the
          increasingly competitive nature of our industry, you might come into
          contact with someone who


                               V.2 November, 2002
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          is interested in acquiring CMC proprietary information. It is critical
          that you do not disclose or distribute that information except as
          authorized by CMC and that you follow all CMC safeguards for
          protecting that information.

     3.5.4.1 Inadvertent Disclosure

          You should be careful to avoid the inadvertent disclosure of
          proprietary information.

          To avoid inadvertent disclosure, never discuss with any unauthorized
          person proprietary information that CMC considers confidential or
          which CMC has not made public. Furthermore, you should not discuss
          such information even with authorized CMC employees if you are in the
          presence of others who are not authorized--for example, at a trade
          show reception or in a public area, such as an airplane, or when using
          a cellular or wireless telephone or an electronic bulletin board or
          database. You should also not discuss such information with family
          members or with friends, who might innocently or unintentionally pass
          the information on to someone else.

          Finally, keep in mind that a harmful disclosure may start with the
          smallest leak of bits of information. Fragments of information you
          disclose may be pieced together with fragments from other sources to
          form a fairly complete picture.

     3.5.4.2 Direct Requests for Information and Contacts with the Press,
     Analysts and Others

          CMC's business activities are monitored closely by reporters, industry
          consultants and securities analysts. You should not initiate contact
          with these individuals or groups or respond to their inquiries without
          authorization as follows:

            Reporters - CMC Chief Financial Officer
            Consultants - CMC Chief Financial Officer
            Securities Analysts - CMC Investor Relations

          Similarly, if you receive a request for information on CMC from an
          attorney, investigator, law enforcement official, or government
          official or agency, you should not respond to their inquiries and
          instead refer the request to CMC's General Counsel or Associate
          General Counsel - Intellectual Property.

          If you do not know what functional area a questioner should be
          referred to, ask your manager before responding.

     3.5.4.3 Using Proprietary Information

          Besides your obligation to protect CMC proprietary information from
          unauthorized disclosure or distribution, you are also required as an
          employee to use such information only in connection with CMC's
          business. This obligation applies whether or not you developed the
          information yourself, and it applies by law in virtually all countries
          in which CMC does business.

     3.5.5 CMC Intellectual Property Rights

          When you joined CMC or its predecessor in interest, or at the time we
          became an independent company, you were required to sign an agreement
          under which you, as an employee of CMC, assumed specific obligations
          relating to intellectual property as well as the treatment of
          confidential information. Among other things in the agreement, you
          assign to CMC all of your right, title, and interest in intellectual
          property you develop. The intellectual property you assign includes
          such things as ideas, inventions, computer programs and documents
          which relate to CMC's actual or anticipated business, research or
          development or that are suggested by, or result from, work or tasks
          you perform for, or on behalf of, CMC. Subject to the laws of each
          country, this obligation applies no matter where or when--at work or
          after hours--such intellectual property is created. You must report
          that intellectual property to CMC, and protect it like any other
          proprietary information of the company. However, if you believe that
          your idea, invention, computer program, or other material neither
          falls within the area of CMC's actual or anticipated business
          interests, nor resulted from, nor was suggested by, any of your work
          assignments at CMC, you should discuss it with CMC's Associate General
          Counsel - Intellectual Property. Throughout your employment with CMC,
          you should receive advice and direction from CMC's Associate General
          Counsel - Intellectual Property before taking any action with respect
          to an invention that may be patentable, and provide her with copies of
          any patent you have applied for or obtained outside of CMC.


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     3.5.6 Leaving CMC

          If you cease to be an employee of CMC for any reason, you must return
          all CMC property, including documents and media which contain CMC
          proprietary information, and you may not disclose or use CMC
          proprietary information, including CMC confidential information. Also,
          CMC's ownership of intellectual property that you created while you
          were a CMC employee continues after you leave the company.

     3.5.7 Legal Remedies

          Regrettably, there have been cases in which CMC's physical, financial
          or intellectual property assets have been wrongfully taken or misused,
          or employees or former employees have violated their agreements with
          CMC with respect to protecting our property or refraining from
          competing against CMC. In some of these instances, CMC has not limited
          its response to disciplinary action against offending employees or
          former employees, but has taken legal action as well. Also,
          individuals can be subject to prosecution for their actions by
          government authorities and convicted of crimes for their part in
          stealing CMC assets.

          CMC will continue to take every step necessary, including legal
          measures, to protect its assets.

3.6  Recording and Reporting Information

     You must record and report all information accurately and honestly.

     Every employee records information of some kind and submits it to the
     company. For example: an engineer fills out a product test report; a
     marketing representative reports orders; an accountant records revenues and
     costs; a scientist prepares a research report; a quality technician
     completes a time-card; and, a product line manager makes an employee
     benefit claim. Each employee must accurately and honestly fill in reports.

     One important report that many employees use is the expense account.
     Employees are entitled to reimbursement for reasonable expenses--but only
     if those expenses were actually incurred. To submit an expense account for
     meals not eaten, miles not driven, airline tickets not used or for any
     other expense not incurred is dishonest reporting and is prohibited.

     Under various laws, such as tax and securities laws, environmental laws, or
     the Foreign Corrupt Practices Act, CMC is required to maintain books and
     records reflecting CMC's transactions. It is essential that these books and
     records are accurate. Regardless of whether reporting is required by law,
     dishonest reporting within CMC, for example to CMC management or CMC
     auditors or during an internal investigation, or to organizations and
     people outside the company, is strictly prohibited. This includes not only
     reporting information inaccurately but also organizing it in a way that is
     intended to mislead or misinform those who receive it. Employees must
     ensure that they do not make false or misleading statements in external
     financial reports, environmental monitoring reports and other documents
     submitted to or maintained for government agencies. Dishonest reporting can
     lead to civil or even criminal liability for you or CMC. Employees who are
     found to have engaged in dishonest reporting, or to have misused their
     positions of authority in this regard, will be subject to disciplinary
     measures, including dismissal.

4.0 DEALING WITH OTHERS OUTSIDE OF CMC

4.1 Bribes, Gifts and Entertainment

     Gifts offered by employees of different companies vary widely. They can
     range from widely distributed advertising novelties of nominal value, which
     you may give or accept, to bribes, which you unquestionably may not give or
     accept.

     Gifts include not only material goods, but also services, promotional
     premiums and discounts.

     The following are CMC's guidelines on giving and receiving gifts and
     business amenities. Exceptions may be approved by an executive officer, but
     those exceptions must not be prohibited by law or known customer business
     practice.



                               V.2 November, 2002
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     4.1.1 Business Amenities

          With management approval, you may give or accept customary business
          amenities, such as meals and entertainment, provided the expenses
          involved are kept at a reasonable level and are not prohibited by law
          or known customer business practice. Suppliers, including CMC,
          frequently find it appropriate to provide education and briefings for
          their customers or suppliers. It is all right to provide or accept
          some services in connection with this type of activity, such as
          transportation, and food and lodging, if you have prior management
          approval.

     4.1.2 Receiving Gifts

          Neither you nor any member of your family may solicit or accept from a
          supplier or customer money or a gift that could influence or could
          reasonably give the appearance of influencing CMC's business
          relationship with that supplier or customer. However, unless CMC has
          specified to the contrary, you may accept promotional premiums and
          discounts offered by transportation companies, hotels, auto rental
          agencies and restaurants if they are based upon membership in bonus
          programs for individuals and are offered to travelers generally.
          Furthermore, you may accept a gift of nominal value, such as an
          advertising novelty, when it is customarily offered to others having a
          similar relationship with the customer or supplier. If you have any
          doubts about a particular situation, you should consult your manager.

          If you are offered a gift which has more than nominal value or which
          is not customarily offered to others, or money, or if either arrives
          at your home or office, tell your manager immediately. Appropriate
          arrangements will be made to return or dispose of what has been
          received, and the supplier or customer will be reminded of CMC's
          policy in this regard.

     4.1.3 Referral Fees

          When authorized by CMC, you may refer customers to third party
          vendors, such as CMC's distributors, transportation and shipping
          entities, or support organizations. However, CMC employees may not
          accept any fee, commission or other compensation for this activity
          from anyone.

     4.1.4 Giving Gifts

          You may not give money or any gift to an executive, official or
          employee (or related person) of any supplier, customer or any other
          organization if doing so would influence or could reasonably give the
          appearance of influencing the organization's relationship with CMC.
          You may, however, provide a gift of nominal value, such as a CMC
          advertising novelty, if it is not prohibited by law or the customer's,
          supplier's or other organization's known business practices.

     4.1.5 Relationships with Government Employees

          When we are dealing with government employees or those who act on the
          government's behalf, practices that are acceptable in the commercial
          business environment, such as providing education, transportation,
          meals, entertainment or other things of value, may be entirely
          unacceptable, and may even violate certain federal, state, local or
          foreign laws and regulations,. Therefore, you must be aware of, and
          adhere to, the relevant laws and regulations governing relations
          between government employees and business entities in every country
          where you conduct business. You should contact the CMC General Counsel
          for guidance.

          You must not give money or a gift to an official or an employee of a
          governmental entity if doing so could be reasonably construed as
          having any connection with CMC's business relationship. U.S. and
          foreign laws often prohibit such actions: for example, the Foreign
          Corrupt Practices Act (FCPA), a U.S. law, makes it a crime to pay
          money or to give anything of value to a foreign official to assist the
          company or another to obtain or retain business with the government,
          whether the improper payment or gift is made directly by a company or
          indirectly through someone acting for the company. Any proposed
          payment or gift to a foreign official, political party or candidate
          must have prior review and approval by the CMC General Counsel, even
          if such payment or gift is common in that country. Keep in mind that
          foreign officials, under the FCPA, can include executives and
          employees of government-owned corporations, such as universities, and
          other entities such as industrial parks. Always ask if you have some
          doubt regarding government ownership or participation.


                               V.2 November, 2002
<PAGE>
          In countries where local customs call for giving gifts to customers or
          others on special occasions, you may, with prior approval from
          management and the CMC General Counsel, present gifts that are lawful,
          appropriate, and of nominal value, provided the action cannot be seen
          as seeking special favor.

          Furthermore, certain legal or ethical restrictions may exist with
          respect to the hiring by CMC of current or former employees of the
          government or their family members. You should consult with the CMC
          General Counsel before any attempts, even preliminary discussions, are
          made to hire any such persons.

     4.1.6 Public Official and Campaign Visits, Speaking Engagements and
     Honoraria

          CMC encourages public officials to make non-partisan visits to CMC
          locations to better understand our company, products, programs and our
          views on public policy issues. However, political campaigning is not
          allowed on CMC property.

          Likewise, public officials, candidates and prominent former officials
          may request or be invited to speak at various CMC events. We generally
          do not pay honoraria or travel expenses since in many instances such a
          payment would not be lawful. You should review any matters in this
          area with CMC's Office of the General Counsel.

4.2 Complying with Laws

     CMC's policy is to comply with all laws and regulations that apply to its
     business. As you conduct CMC's business, you may encounter a variety of
     legal issues, particularly in the areas described below. If you have
     questions on specific laws or regulations, contact CMC's Office of the
     General Counsel.

     4.2.1 Competition

          Laws governing competition exist in most of the countries in which CMC
          does business. The purpose of competition laws, which also may be
          known as antitrust, monopoly, fair trade or cartel laws, is to prevent
          interference with the functioning of a competitive market system.
          While the purpose of such laws is primarily economic, their effect is
          often seen as going beyond consumer or customer welfare to protecting
          other values of society, including individual freedoms.

          Under these laws, companies may not enter into agreements with other
          companies, including their distributors and competitors, however
          informally, that unreasonably restrict the functioning of the
          competitive system, such as price fixing, or dividing customers or
          territories.

          Companies also may violate competition laws without acting jointly
          with other companies by, for example, illegally monopolizing or
          attempting to monopolize an industry or unlawfully abusing a dominant
          position through arrangements such as "tie-in", certain pricing, or
          exclusive dealing arrangements.

          CMC's policy is to comply fully with competition laws throughout the
          world. You can help by adhering to CMC's Code of Business Conduct and
          related policies and procedures, by being sensitive to legal concerns
          under competition laws, and by raising any such concerns with CMC's
          General Counsel.

     4.2.2 Export

          It is CMC's policy to comply with the export control laws and
          regulations of all countries in which we do business. When certain CMC
          products and technical data are exported, CMC may have to obtain an
          export authorization from the U.S. or appropriate foreign government.

          It is against the law to export without authorization or to facilitate
          the unauthorized export of CMC technology. Penalties for failure to
          comply with export laws and regulations are severe and can result in
          fines, loss of export privileges for our products and imprisonment. If
          you have questions on export-related issues, talk with your manager or
          the CMC General Counsel.

     4.2.3 Antiboycott

          U.S. law prohibits CMC and its subsidiaries and affiliates and their
          agents from complying with or supporting a foreign country's boycott
          of a country that is "friendly" to the United States. CMC is also
          required to report promptly to the U.S. Government any request to
          support a boycott or to furnish information concerning a boycott. A
          foreign country or an entity associated with the country could make
          such a request in writing, orally in

                               V.2 November, 2002
<PAGE>

          connection with a transaction or in a number of other ways. Examples
          of improper boycott requests are requests that we refuse to do
          business with a boycotted country, including its corporation and
          citizens, or with so-called blacklisted companies who do business with
          the boycotted country or that we provide information about activities
          in a boycotted country or implement letters of credit with boycott
          conditions. If you hear of a boycott or receive a request to support a
          boycott or to provide information related to a boycott, you should
          contact CMC's General Counsel.

     4.2.4 Import

          As an importer, CMC must comply with import regulations and
          requirements when engaging in international trade. Because of the
          continued globalization of CMC's business, there are many situations,
          some of them very subtle, in which your work may have import
          implications. For example, in addition to the obvious one in which you
          are importing raw materials, parts or products into the U.S. or
          another country, there may be import implications in activities, --
          such as development process activity requiring non-U.S. sourcing,
          customer activity requiring the shipment of products to another
          country, or the shipment of samples. In addition, experience has shown
          that designing parts and ensuring accuracy of inventory of parts will
          have import implications whenever those parts will cross international
          borders. You need to be aware of import regulations and requirements,
          especially if you are involved in importing. A failure to comply with
          the law can result in fines, penalties, imprisonment and/or a loss of
          import privileges. If you have questions about imports, contact your
          manager, Manager of Planning and Distribution, or the Office of the
          General Counsel.

     4.2.5 Safety, Health and the Environment

          CMC is committed to leadership in safety, health and environmental
          protection. Not only will we comply with all safety, health and
          environmental laws in the countries in which we operate, but if there
          is no law or if the law does not protect the safety and health of our
          employees and the environment, we will set and adhere to stringent
          standards of our own. Each of us must comply with safety, health and
          environmental laws and CMC's related policies.

          If you are involved with processes that affect the environment, such
          as measuring, recording or reporting discharges and emissions to the
          environment or handling hazardous wastes, you must be sure to comply
          with environmental regulations and permits. You must also maintain CMC
          standards and ensure that reports are accurate and complete.

          As an employee, you have a role to play in working in a manner that
          supports your own safety and health and that of others, as well as in
          protecting the environment. If you become aware of any violation of
          safety, health or environmental law or any action that may appear to
          conceal such a violation, you should immediately report the matter to
          your manager, CMC's Director, Safety, Health and Environment, or to
          CMC's General Counsel.

     4.2.6 Lobbying

          Any contact with government personnel for the purpose of influencing
          legislation or rule making, including how CMC operates in a particular
          country or locality, is considered lobbying. Some laws also define
          lobbying even more broadly to include our normal marketing activities.
          You are responsible for knowing and adhering to all the relevant
          lobbying laws and associated gift laws, if applicable, and for
          compliance with all reporting requirements.

          In general, any and all lobbying activity related to CMC is
          coordinated through CMC's General Counsel. You must obtain the prior
          approval of CMC's General Counsel to lobby or authorize anyone else
          (for example, a consultant or agent) to lobby on CMC's behalf.

     4.2.7 Disclosure Obligations

          The policy of CMC is to provide full, fair, accurate, timely and
          understandable disclosure in reports and documents that CMC submits to
          or files with the Securities and Exchange Commission, other regulatory
          bodies, and in other public communications made by us. The accuracy
          and timeliness of public disclosure can have an impact on the
          investment decisions of hundreds of investors. CMC's executive,
          financial, and accounting officers are responsible for assuring that
          the information we release to the public is free from material
          misstatements, omissions, or inaccuracies, but you must also do your
          part. Your first responsibility is to assure that all of our business
          is conducted in accordance with our Vision and Values and with this
          Code of Business Conduct . If you become aware of any facts or
          circumstances that cause you to believe that any information that has
          been or will be released to the public contains material
          misstatements, omissions, or inaccuracies, you are encouraged and


                               V.2 November, 2002
<PAGE>

          expected to contact CMC's General Counsel, CEO, or CFO to discuss the
          matter. See Section 3.1. Communications Channels, for a complete
          description of the channels open to you to express any concerns about
          this or other matters covered by this Code or otherwise.

5.0 FURTHER GUIDANCE REGARDING WORKING WITH CUSTOMERS, SUPPLIERS AND OTHER
OUTSIDE PARTIES

You must be ethical and lawful in all of your business dealings whether you are
selling, buying or representing CMC in any other capacity.

Today CMC is engaged in a variety of business relationships with other companies
and organizations, including customers, suppliers, distributors, and
co-suppliers/original equipment manufacturers. No matter what type of
organization you are dealing with or what its relationship is to CMC, you should
always observe the following general standards.

5.1  Avoiding Misrepresentation

     Never make misrepresentations or dishonest statements to anyone. If you
     believe that the other person may have misunderstood you, promptly correct
     any misunderstanding. Honesty based on clear communication is integral to
     ethical behavior. The resulting trustworthiness is essential to forming and
     maintaining sound, lasting relationships.

5.2  Dealing with Suppliers

     In deciding among competing suppliers, we weigh the facts impartially to
     determine the best supplier. You should do so whether you are in a
     purchasing job, a local office or any other part of our business, and
     without regard to the type or volume of transaction.

     Whether or not you are in a position to influence decisions involving the
     evaluation or selection of suppliers, you must not exert or attempt to
     exert influence to obtain "special treatment" for a particular supplier.
     Even to appear to do so can undermine the integrity of our established
     procedures. CMC uses an evaluation process to select the best suppliers.
     Prices and other information submitted by suppliers and our evaluation of
     that information are confidential to CMC. Employees and former employees
     may not use any of this information outside of CMC without written
     permission from management. It is essential that suppliers competing for
     our business have confidence in the integrity of not only our selection
     process but also our working relationship with them once they have been
     selected as a supplier.

     5.2.1 Avoiding Reciprocal Dealing

          Seeking reciprocity is contrary to CMC policy and may also be
          unlawful. You should not tell a prospective supplier that your
          decision to buy its goods or services is conditioned on the supplier's
          agreement to buy CMC products or services.

          This does not mean that a customer of CMC cannot be a supplier to CMC
          or that CMC can never consider its other relationships with the
          supplier when it is evaluating the supplier. It simply means that
          CMC's decision to buy from a supplier must be made independently from
          that supplier's decision to buy from CMC.

5.3  Competing in the Field

     CMC will compete vigorously for business. If circumstances require modified
     pricing or service or support terms, the modifications must be specifically
     approved by the appropriate level of management. Never extend any modified
     contract terms to any customer without prior authorization.

     If you are performing a marketing or customer service or support activity,
     CMC expects you to compete not just vigorously and effectively, but
     lawfully and ethically as well.

     5.3.1 Working with Customers and Avoiding False and Misleading Statements
     about Competitors

          It is CMC's policy to sell our products and offerings on their merits,
          enabling our customers to make their choices in an unrestrained
          manner, based on accurate information. Never force, or suggest that it
          is a requirement that our customers take other CMC products or
          offerings as a condition of delivery of the desired product or
          offering. In addition, we will not sell a product on the condition
          that the customer will not use or purchase the products of a
          particular competitor. Also, false or misleading statements and
          innuendoes about competitors, their products or


                               V.2 November, 2002
<PAGE>

          their offerings are improper. All of this type of conduct only invites
          disrespect from customers and complaints from competitors.

          Be sure that all comparisons to competitors and their products and
          offerings are substantiated, and that they are complete, accurate and
          not misleading whenever they are made. Certain countries prohibit
          comparative advertising. Advice on this subject is available from the
          Office of the General Counsel.

5.4  Relationships with Other Organizations

     Frequently, other organizations have multiple relationships with CMC. For
     example, a co-supplier/original equipment manufacturer may be both an end
     user and a competitor. Another organization may be a CMC supplier and
     Customer at the same time, or a supplier to us in one aspect of its
     business and a competitor in another. Still another organization may be an
     agent for our customer (for example, a third party chemical manager), and
     also a competitor to us. In any dealings, it is important that you
     understand each one of the relationships involved, and act accordingly.

     5.4.1 Complementary Third Parties

          CMC has various relationships with complementary third parties, such
          as distributors and sales representatives, to help CMC market and
          support CMC's products and offerings, and those relationships are
          governed by the arrangements we have with those third parties as well
          as relevant law in many countries. If your responsibilities bring you
          into contact with these third parties, and you have questions about
          how to work with them, please contact the Office of the General
          Counsel.

     5.4.2 Business Contacts with Competitors

          It is important to recognize when a company you are dealing with, as a
          supplier, customer, or agent to a customer of ours, is also a CMC
          competitor. Such relationships require extra care. It is inevitable
          that you and competitors will, from time to time, meet, talk and
          attend the same industry or association meetings. Many of these
          contacts are perfectly acceptable as long as you follow established
          procedures. Acceptable contacts include: sales to other companies in
          our industry and purchases from them; approved participation in joint
          meetings or interactions with mutual customers; and attendance at
          business shows, standards organizations and trade associations. But
          even these contacts require caution. If in doubt, you should seek
          advice from the Office of the General Counsel.

     5.4.3 Prohibitions

          In all contacts with competitors, do not discuss pricing policy,
          contract terms, costs, inventories, marketing and product plans,
          market surveys and studies, production plans and capabilities,
          arrangements with, or identity of, suppliers --and, of course, any
          other proprietary or confidential information.

          Discussion of these subjects or collaboration on them with competitors
          can be illegal. If a competitor raises any of them, even lightly or
          with apparent innocence, you should object, stop the conversation
          immediately, and tell the competitor that under no circumstances will
          you discuss these matters. If necessary, you should leave the meeting.

          In summary, disassociate yourself and CMC from participation in any
          possibly illegal activity with competitors; confine your communication
          to what is clearly legal and proper. Finally, report immediately to
          the CMC General Counsel any incident involving a prohibited subject.

5.5  Acquiring and Using Information about Others

     In the normal course of business, it is not unusual to acquire information
     about many other organizations, including competitors. Doing so is a normal
     business activity and is not unethical in itself. In fact, CMC quite
     properly gathers this kind of information for such purposes as evaluating
     suppliers and creditworthiness. We also collect information on competitors
     from a variety of legitimate sources to evaluate the relative merits of
     their products, services, and marketing methods. This activity is proper
     and necessary in a competitive system.

     There are, however, limits to the ways that information should be acquired
     and used, especially information about competitors. No company should use
     improper means to acquire a competitor's trade secrets or other
     confidential information. Illegal practices such as trespassing, burglary,
     wiretapping, bribery and stealing are obviously wrong; so


                               V.2 November, 2002
<PAGE>

     is attempting to acquire a competitor's confidential information from the
     competitor's employees or CMC's customers. CMC will not tolerate any form
     of questionable intelligence-gathering.

     Information about other companies, especially that of our customers and
     suppliers, should be treated with sensitivity and discretion. Such
     information is often about individuals. Other companies are rightly
     concerned about their proprietary information, reputations and the privacy
     of their people.

     In addition, individuals, such as the employees of customers and suppliers,
     are also concerned about their privacy, especially now that Internet use
     has become so widespread. CMC remains committed to protecting the privacy
     of personal information of others. CMC will only collect, use, process, and
     disclose an individual's personal information in accordance with our
     privacy policies and guidelines.

     When working with sensitive information about other companies and
     individuals, you should use that information in the proper context and make
     it available only to other CMC employees with a legitimate need to know. In
     presenting such information, you should disclose the identity of the
     organization or individuals only if necessary. If disclosure is not
     necessary, you should present the information in the aggregate or by some
     other means.

5.6  Information Owned by Others

     Like CMC, other organizations and some individuals have intellectual
     property, including confidential information, they want to protect. They
     are sometimes willing to disclose and allow others to use their proprietary
     information for a particular purpose. If you receive another party's
     proprietary information, you must proceed with caution to prevent any
     accusations that CMC misappropriated or misused the information.

     5.6.1 Receiving Information that May Be Confidential or Have Restrictions
     on Its Use

          To avoid the risk of CMC being accused of misappropriating or misusing
          someone's confidential or restricted information, there are certain
          steps you must take before receiving such information. The receipt of
          confidential or restricted information (whether oral, visual or
          written) must not take place until the terms of its use have been
          formally agreed to by CMC and the other party in a written agreement
          approved by CMC's Associate General Counsel - Intellectual Property.
          Once another party's confidential or restricted information is
          properly in your hands, you must not use, copy, distribute or disclose
          that information unless you do so in accordance with the terms of the
          agreement.

          In any case, do not take the status of information for granted. If you
          have information in your possession that you believe may be
          confidential to a third party or may have restrictions on its use, you
          should consult immediately with CMC's Associate General Counsel -
          Intellectual Property.

     5.6.2 Acquiring Software

          Special care should be taken in acquiring software from others. As
          intellectual property, software is protected by copyright, and may
          also be protected by patent or trade secret laws. Software includes
          computer programs in "beta" or finished form, databases and related
          documentation. The software may be on CD-ROMs or diskettes or it may
          reside on electronic online bulletin boards or databases. Before you
          accept software, access software or data on a network, or accept a
          license agreement, you must review the matter with CMC's Associate
          General Counsel - Intellectual Property. The terms and conditions of
          any license agreement--such as provisions not to copy or distribute
          programs--must also be strictly followed. If you acquire software for
          your personally owned equipment, you should not copy any part of such
          software in any work you do for CMC or place such software on any
          CMC-owned computer system. This includes any copies of software which
          reside on any electronic online bulletin boards or databases.

          It is your responsibility to make sure that all third party software
          you are using is appropriately licensed and that you use it only in
          accordance with the terms of its license.

     5.7 Using Trademarks

          CMC and many other companies have trademarks--words, names, symbols or
          devices--that are used to identify and distinguish the company's
          products. Two of CMC's most prominent trademarks are our logo and
          name, Cabot Microelectronics. Some trademarks are registered in the
          U.S. Patent and Trademark Office; others are not. For example, "iCue"
          is a registered trademark of CMC, indicated by an "(R)". There are
          other trademarks of


                               V.2 November, 2002
<PAGE>

          CMC that are not yet registered, for example, "LUSTRA". Its trademark
          status is indicated by "TM". There may be additional or different
          trademark designations outside of the U.S.

          In all countries, it is important that you properly acknowledge and
          use CMC trademarks and the trademarks of other companies.
          Specifically, you should always ensure that the trademark is spelled
          correctly and written the way the owner of the trademark writes it.
          You should not use the trademark as a generic name and should use the
          trademark only as an adjective. Also, you should indicate the first
          time the trademark is mentioned in a publication that it is a
          trademark of CMC or of the company who owns it.

          You should consult CMC's Associate General Counsel - Intellectual
          Property if you have questions on the proper use of a trademark.

6.0 YOUR OWN ACTIVITIES

6.1 Conflicts of Interest

     Your private life is very much your own. Still, a conflict of interest may
     arise if you engage in any activities or advance any personal interests, at
     the expense of CMC's interests. It's up to you to avoid situations in which
     your loyalty may become divided. Each individual's situation is different,
     and in evaluating your own, you will have to consider many factors. The
     most common types of conflicts are addressed here to help you make informed
     decisions. You should consult with CMC's General Counsel if you have any
     questions about these matters.

     6.1.1 Assisting a Competitor or Other Organizations

          An obvious conflict of interest is providing assistance to an
          organization that markets products and offerings in competition with
          CMC's current or potential products or offerings. You may not work for
          such an organization in any capacity, such as an employee, a
          consultant or as a member of its board of directors; you may not hold
          more than a nominal financial interest in such an organization if it
          is publicly traded, and not hold any interest if it is privately held.
          Such activities are prohibited because they could divide your loyalty
          between CMC and that organization.

          In addition, you may not serve as a member of the board of directors
          of any for-profit entity, whether publicly or privately held, without
          prior approval from the CMC General Counsel.

     6.1.2 Competing against CMC

          Employees should be careful to avoid activities that conflict with
          CMC's business interests.

          Obviously, you may not commercially market or develop products or
          services in competition with CMC's current or potential products or
          offerings. Such activities are "commercial" if you receive direct or
          indirect remuneration of any kind. In addition, certain non-commercial
          activity, such as research collaborations with universities or
          consortiums, also might conflict with CMC's business interests.

          Because CMC is expanding into new lines of business and new areas of
          interest, the company will redraw lines of acceptable activity on an
          ongoing basis. It is unlikely that you will find definitive answers to
          many of your questions regarding the boundaries of acceptable activity
          in published guidelines. It is therefore your responsibility to
          consult with your management or the Office of the General Counsel to
          determine whether your planned activity will compete with any of CMC's
          actual or potential businesses. This should be done before you pursue
          any activity that might create a conflict of interest or the
          appearance of a conflict of interest with CMC.

     6.1.3 Supplying to or Other Relationships with CMC

          Unless approved in advance by an executive officer and CMC's General
          Counsel, you may not be a supplier of any kind of product or services
          to CMC, represent a supplier to CMC, work for a supplier to CMC, hold
          more than a nominal financial interest in a supplier, or be a member
          of its board of directors while you are an employee of CMC. In
          addition, you may not accept money or benefits of any kind for any
          advice or services you may provide to a supplier in connection with
          its business with CMC. These same prohibitions also apply to your
          dealings with any entity with whom CMC does business.


                               V.2 November, 2002
<PAGE>

     6.1.4 Other Personal Financial Interests

          In addition to the restrictions discussed above, you should not have
          any financial interest in any organization with whom CMC does business
          or competes if that interest would give you or would appear to give
          you a conflict of interest with CMC. Such organizations include
          suppliers, competitors, customers, distributors and
          co-suppliers/original equipment manufacturers. You should consult with
          CMC's General Counsel if you have any questions remaining after
          considering the following:

          6.1.4.1 Publicly Traded Securities

               To determine whether an improper interest exists, ask yourself
               the following questions:
               -    What is the extent of the competition or the nature of the
                    relationship between CMC and the other company?
               -    If the other company is in more than one line of business,
                    how significant is the part that competes with or supplies
                    CMC?
               -    What is the size of my investment in relation to my salary
                    and other family income, including income from other
                    investments?
               -    Is it significant enough to cause me to take some action as
                    a CMC employee to protect or enhance my investment?
               -    Given the nature of my job in CMC, could my actions as a CMC
                    employee affect the value of my investment in the other
                    company (for example, do you have anything to do, either
                    directly or indirectly, in deciding whether CMC does
                    business with that company)?
               -    Could my actions significantly enhance my investment, even
                    if it is a relatively modest one?

               A financial interest is improper if your job, the amount of your
               investment, or the particular company in which you invested
               could--when viewed objectively by another person--influence your
               actions as a CMC employee.

               Additionally, from time to time, an existing or prospective CMC
               supplier, distributor or customer may offer stock options or
               other securities to a select small group of investors in
               connection with the company's initial public offering. You should
               not accept or buy any of that company's securities in such a
               situation without receiving prior approval from CMC's General
               Counsel.

               You should not evade these guidelines on investments by acting
               indirectly through anyone else.

          6.1.4.2 Privately Held Organizations

               Investments in privately (sometimes referred to as "closely")
               held organizations--typically, privately held corporations,
               partnerships or even sole proprietorships--raise additional
               concerns over those in publicly traded companies because of the
               closer ties of investors to most privately held organizations.
               For example, there are generally relatively few investors or
               owners of such companies, giving each a greater stake in
               ownership; the investors often have a chance to participate in
               the company's day-to-day operations; and the investors may be
               perceived to be closely identified with the company.

               This relatively close relationship may give the appearance to
               competitors of the privately held organization that it derives
               some benefit from CMC. Such a relationship may also give the
               appearance to CMC employees that the investing employee is using
               CMC's time, facilities or confidential information for the
               benefit of the privately held company. For these reasons,
               employees may not make any investment in a privately held
               organization that is a competitor, supplier, distributor,
               customer or other organization with whom CMC does business.

6.2 Using Inside Information and Insider Trading

     In the course of your employment with CMC, you may become aware of
     information about CMC or other companies that has not been made public. The
     use of such nonpublic or "inside" information about CMC or another company
     for your financial or other benefit not only is unethical, but also may be
     a violation of law. U.S. law makes it unlawful for any person who has
     "material" nonpublic information about a company to trade the stock or
     other securities of the company or to disclose such information to others
     who may trade. Violation of such laws may result in civil and criminal
     penalties, including fines and jail sentences. CMC will not tolerate the
     improper use of inside information. These prohibitions also apply outside
     the U.S.


                               V.2 November, 2002
<PAGE>

     Material inside information is information which is not available to the
     general public and which could influence a reasonable investor to buy, sell
     or hold stock or securities. While it is not possible to identify in
     advance all information that could be viewed as material inside
     information, some examples might include nonpublic information about: CMC's
     financial performance including earnings and actions related to its stock;
     acquisitions or other business combinations; divestitures; major new
     product announcements; significant advances in research; significant
     contracts or the loss of them; and, other significant activities affecting
     CMC. Here are some examples of how you can avoid the improper use of inside
     information:

          -    If you know that CMC is considering an alliance or is about to
               announce a new product or make a purchasing decision that could
               affect the price of the stock of a CMC supplier or other company,
               you should not buy or sell the stock of that company until after
               the information becomes public.
          -    Similarly, if you know that CMC is about to make an announcement
               that could affect the price of its own stock, you should not buy
               or sell CMC stock on the open market until after the
               announcement.
          -    You should not buy or sell the stock of a customer or other
               company with whom CMC does business based on any inside
               information you have about that company.
          -    If you have nonpublic information that CMC is about to build a
               new facility or expand an existing facility, you should not
               invest in land or in any business near the new site.
          -    You should not disclose inside information to CMC employees who
               do not have a business need to know or to anyone outside of CMC.

     CMC's directors, officers, and other key employees are also subject to
     additional responsibilities and guidelines with respect to trading in CMC's
     stock, such as a prohibition on trading during quarterly "blackout"
     periods.

     As with investments, you should not evade these guidelines by acting
     through anyone else or by giving inside information to others for their use
     even if you will not financially benefit from it.

     If you have any doubt about what you can or cannot do in this area, you
     should consult with CMC's General Counsel.

6.3  Using CMC's Time and Assets

     You may not perform non-CMC work or solicit such business on CMC premises
     or while working on CMC time, including time you are given with pay to
     handle personal matters. Also, you are not permitted to use CMC assets,
     including equipment, information systems, telephones, materials, resources
     or proprietary information for any outside work.

6.4  Public Service

     CMC encourages employees to be active in the civic life of their
     communities. However, such service may, at times, place you in a situation
     that poses a conflict of interest with CMC. As a board or committee member,
     you may, for example, be confronted with a decision involving CMC. It might
     be a decision by a board of tax assessors or a zoning board that affects
     CMC property. In such circumstances, your interest in CMC and your
     obligation to the civic organization might pull you in opposite directions.
     The law may require you to abstain, depending on your position in CMC and
     whether you stand to gain personally from the decision. On the other hand,
     there may be circumstances in which the law does not permit you to abstain.
     While you are in the best position to make the decision and bear the
     responsibility for the decision, before making your decision, you should
     get advice from the civic organization's lawyer and from the Office of the
     General Counsel. In order to protect CMC from embarrassment or other
     issues, whether or not you finally abstain, you should make it clear that
     you are a CMC employee and thereby head off any charges of trying to
     conceal your association with CMC. If you decide to abstain, state clearly
     that you are doing so because there would be a conflict of interest--or the
     appearance of one--if you did not.

6.5  Participation in Political Life

     CMC will not make contributions or payments or otherwise give any
     endorsement of support which would be considered a contribution directly or
     indirectly to political parties or candidates, including through
     intermediary organizations, such as political action committees or campaign
     funds. For example, CMC will not purchase tickets or pay fees for you or
     anyone else to attend any event where any portion of the funds will be used
     for election campaigns. In many countries, political contributions by
     corporations are illegal. CMC will not make such contributions, even in
     countries where they are legal. Also, the company will not provide any
     other form of support that may be considered a contribution.

     You must not make any political contribution as a representative of CMC.
     You may not request reimbursement from CMC, nor will CMC reimburse you, for
     any personal contributions you make. In addition, you should recognize that


                               V.2 November, 2002
<PAGE>

     your work time or use of CMC assets is the equivalent of such a
     contribution. Therefore, you will not be paid by CMC for any time spent
     running for public office, serving as an elected official or campaigning
     for a political candidate, unless required by law. You can, however, take
     reasonable time off without pay for such activities if your CMC duties
     permit the time off and it is approved by your manager. You also may use
     vacation time for political activity.

     6.5.1 Speaking Out

          When you speak out on public issues, make sure that you do so as an
          individual. Don't give the appearance that you are speaking or acting
          on CMC's behalf.

6.6  Someone Close to You Working in the Industry

     With the growth in two-career families and the expansion of our industry,
     you may find yourself in a situation where your spouse, another member of
     your immediate family or someone else you are close to is a competitor or
     supplier of CMC or is employed by one. While everyone is entitled to choose
     and pursue a career, such situations call for extra sensitivity to
     security, confidentiality and conflicts of interest. The closeness of the
     relationship might lead you to inadvertently compromise CMC's interests.

     There are several factors to consider in assessing such a situation. Among
     them are the relationship between CMC and the other company, the nature of
     your responsibilities as a CMC employee and those of the person close to
     you, and the access each of you has to your respective employer's
     confidential information.

     If you have any questions about your situation, you should review it with
     your manager to assess the nature and extent of any concern and how it can
     be resolved. Frequently, any risk to CMC's interests is sufficiently remote
     that your manager need only remind you to guard against inadvertently
     disclosing CMC confidential information. However, in some instances, a
     change in the job responsibilities of one of the people involved may be
     necessary.

7.0 SOME ADDITIONAL GUIDANCE

As already stated, while this Code of Business Conduct provides you with basic
guidelines for performing your responsibilities as a CMC employee in a lawful
and ethical way and in conjunction with CMC's Vision and Values, it cannot serve
as a definitive statement for each situation that you may encounter as a CMC
employee. If you are in doubt about a particular business conduct situation, you
might ask yourself the following questions:

          -    Is it legal?
          -    Does it violate CMC's policy?
          -    Is it consistent with CMC's Vision and Values?
          -    Is it fair and just? How does it make me feel about myself?
          -    What would my family think about it?
          -    How would it look in a newspaper article?
          -    Will I sleep soundly tonight?
          -    What would I tell a child to do?

If you are unsure about what to do, ask questions - contact your manager, a more
senior-level manager, the Human Resources Department or the Office of the
General Counsel.

To keep pace with the complexity and change that is an ongoing part of our
business and industry, we will maintain this Code of Business Conduct online and
update it on an ongoing basis as necessary. Employees also need to comply with
CMC's employee policies and procedures, and employees who work with particular
matters - for example, safety, health and environment, human resources, finance,
export/import - also may have additional guidelines to follow.

Any exceptions to CMC's Code of Business Conduct for CMC employees other than
Directors or Executive Officers must be specifically approved by CMC's Chief
Compliance Officer, who is CMC's General Counsel; any exceptions for Directors
or Executive Officers must be specifically approved by the Board of Directors of
CMC.



                               V.2 November, 2002

<PAGE>
                     CODE OF BUSINESS CONDUCT CERTIFICATION

I acknowledge that I have received and will comply with Cabot Microelectronics
Corporation's Code of Business Conduct. I understand that if I have questions
related to the Code of Business Conduct, or become aware of any violations of
it, I need to discuss them promptly with my manager, any other CMC manager, the
Human Resources Department, CMC counsel, including CMC's General Counsel, who is
CMC's Compliance Officer, or CMC's Internal Audit Manager, call the Ethics Line
at 630/499-2702, send an email to Ethics_Email@cabotcmp.com, or contact any
member of CMC's Board of Directors, including any member of the Audit Committee
of the Board.







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                               V.2 November, 2002