**Exhibit 31.3**
CERTIFICATION UNDER EXCHANGE ACT RULE 13A-14 AND 15D-14
I, William R. McClayton, certify that:
1. I have reviewed this annual report on Form 10-K of DiamondClusterInternational, Inc; 2. Based on my knowledge, this annual report does not contain any untruestatement of amaterial fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which such statementswere made, not misleading with respect to the period covered by this annualreport; 3. Based on my knowledge, the financial statements, and other financialinformation included in this annual report, fairly present in allmaterial respects the financial condition, results of operations and cashflows of the registrant as of, and for, the periods presented in thisannual report; 4. The registrant’s other certifying officers and I are responsible forestablishing and maintaining disclosure controls and procedures (asdefined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internalcontrol over financial reporting (as defined in Exchange Act Rules13-15(f) and 15d-15(f)) for the registrant and we have:
 a) Designed such disclosure controls and procedures to ensure thatmaterial information relating to the registrant, including itsconsolidated subsidiaries, is made known to us by others within thoseentities, particularly during the period in which this annual report isbeing prepared;  b) Designed such internal control over financial reporting, or causedsuch internal control over financial reporting to be designed under oursupervision, to provide reasonable assurance regarding the reliabilityof financial reporting and the preparation of financial statements forexternal purposes in accordance with generally accepted accountingprinciples;  c) Evaluated the effectiveness of the registrant’s disclosurecontrols and procedures and presented in this report our conclusionsabout the effectiveness of the disclosure controls and procedures, as ofthe end of the period covered by this report based on such evaluation;and  d) Disclosed in this report any change in the registrant’s internalcontrol over financial reporting that occurred during the registrant’smost recent fiscal quarter (the registrant’s fourth fiscal quarter inthe case of an annual report) that has materially affected, or isreasonably likely to materially affect, the registrant’s internalcontrol over financial reporting.
5. The registrant’s other certifying officers and I have disclosed, basedon our most recent evaluation of internal control over financialreporting, to the registrant’s auditors and the audit committee ofregistrant’s board of directors (or persons performing the equivalentfunctions):
 a) All significant deficiencies and material weaknesses in the designor operation of internal controls over financial reporting which arereasonably likely to adversely affect the registrant’s ability torecord, process, summarize and report financial information; and  b) Any fraud, whether or not material, that involves management orother employees who have a significant role in the registrant’sinternal controls over financial reporting.
Date: June 7, 2004
/s/ William R. McClaytonBy: William R McClaytonIts: Senior Vice President, Finance and Administration
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