Exhibit 10.a.
                                                          As amended on 4/28/97

                                   CDI CORP.
         NON-QUALIFIED STOCK OPTION AND STOCK APPRECIATION RIGHTS PLAN


1.  Purpose.  The purpose of this plan  ("Plan") is to provide a more  effective
method of compensating employees,  consultants and directors of the Company than
is  currently  available  and to  complement  the other  incentive  plans of the
Company,  thus  encouraging  greater  personal  interest  in the  success of the
Company  on the  part of such  personnel  and  furnishing  them  with a  further
incentive  to remain  with the  Company  and to  increase  their  efforts on its
behalf.

2. Definitions:

(a) "Board" means the board of directors of the Parent Company.

(b) "Committee" means the committee described in Paragraph 5.

(c) "Company" means CDI Corp. and each of its Subsidiary Companies.

(d) "Date of  Exercise"  means the date on which notice of exercise of an Option
or SAR is delivered to the Parent Company.

(e) "Date of Grant" means the date on which an Option or SAR is granted.

(f) "Eligible Director" means any Non-Employee  Director except a director whose
compensation for service on the Board is included in the income of a corporation
or partnership of which the director is an employee or partner.

(g) "Fair Market Value" means the closing price of actual sales of Shares on the
New York Stock  Exchange  on a given date or, if there are no such sales on such
date, the closing price of the Shares on such Exchange on the last date on which
there was a sale.

(h)  "Holder"  means a person to whom an SAR not  attached to an Option has been
granted under the Plan,  which SAR has not been exercised and has not expired or
terminated.

(i) "Non-Employee  Director" means any director of the Parent Company who is not
a full-time employee of the Parent Company or any Subsidiary Company.

(j)  "Option"  means a  non-qualified  stock option  granted  under the Plan and
described in Paragraph 4(a).

(k)  "Optionee"  means a  person  to whom an  Option  or an  Option  with an SAR
attached  has been  granted  under  the Plan,  which  Option or SAR has not been
exercised and has not expired or terminated.

(l) "Parent Company" means CDI Corp.

<PAGE>

(m)  "Retainer  Fee"  means the annual  retainer  fee  payable  to  Non-Employee
Directors for their service as directors of the Parent Company during a Retainer
Fee Year. A Retainer Fee does not include attendance or committee fees.

(n)  "Retainer Fee Option"  means an Option  granted to an Eligible  Director in
payment of such Eligible Director's Retainer Fee pursuant to Paragraph 6.

(o) "Retainer  Fee Year" means the one year period  between  consecutive  annual
meetings  of the  shareholders  of the  Parent  Company,  beginning  on the date
immediately following the annual meeting.

(p) "SAR" means a stock  appreciation right granted under the Plan and described
in Paragraphs 4(b) or 4(c).

(q) "Shares"  means  shares of common  stock,  par value $.10 per share,  of the
Parent Company.

(r) "Subsidiary Company" means any corporation  controlled by the Parent Company
or by a  subsidiary  controlled  by the  Parent  Company  ("control"  having the
meaning  set  forth  in  Section   368(c)  of  the  Internal   Revenue  Code  or
corresponding provisions of successor laws), provided that if the corporation is
controlled by a subsidiary of the Parent Company, either the Parent Company must
own 100% of the stock of the subsidiary or the  subsidiary  must own 100% of the
stock of the corporation.

(s) "Value" of an SAR shall mean the excess of the Fair Market  Value of a Share
on the Date of Exercise  over an amount  fixed by the  Committee  on the Date of
Grant (the "SAR Reference Price"); provided that the SAR Reference Price may not
be less than 50% of the Fair Market Value of a Share on the Date of Grant. Where
an SAR is attached to an Option,  the SAR Reference  Price shall be equal to the
Option price of one Share under the attached Option.

3.  Shares  Subject  to the Plan.  On and after  April 30,  1991,  not more than
1,600,000  Shares may be  delivered  pursuant to the exercise of Options or SARs
under the Plan. The Shares so delivered may, at the election of the Company,  be
either  treasury  Shares or Shares  originally  issued for the purpose.  When an
Option is granted  (whether  or not  attached  to an SAR),  the number of Shares
subject  to such  Option  shall  be  reserved  for  issuance  out of the  Shares
remaining  available  for grant  under the Plan.  When SARs not  attached  to an
Option are granted, there shall be reserved for issuance thereunder Shares in an
amount  equal to  one-half  of the  number of SARs  granted.  If Options or SARs
granted under the Plan terminate or expire  without being  exercised in whole or
in part, other Options or SARs may be granted covering the Shares not delivered.
No individual shall be eligible to receive, in any one calendar year, Options or
SARs with  respect  to more than  400,000  Shares  (which  number is  subject to
adjustment as provided in Paragraph 15 hereof).

4. Rights to be Granted. Rights which may be granted under the Plan are:

(a) Options,  which give the  Optionee the right for a specified  time period to
purchase a specified number of Shares at a specified price;

(b) SARs,  which are  attached to Options and which give the  Optionee the right
for a specified  time period,  without  payment to the  Company,  to receive the

<PAGE>

Value of such SARs, to be paid in cash and Shares in accordance with Paragraph 9
below, in lieu of purchasing Shares under the related Option; and

(c) SARs,  which are not attached to Options and which give the Holder the right
for a specified  time period,  without  payment to the  Company,  to receive the
Value of such SARs, to be paid in cash and Shares in accordance with Paragraph 9
below.

5. Administration. The Plan shall be administered by the Stock Option Committee,
which  shall be composed of not less than two  directors  of the Parent  Company
appointed  by the  Board.  No  director  serving on the  Committee  shall (a) be
eligible to be granted  Options or SARs under the Plan except for  Retainer  Fee
Options,  or to be selected as a participant under any other  discretionary plan
of the Company or any of its affiliates  entitling them to acquire stock,  stock
options or stock appreciation rights of the Company or any of its affiliates, or
(b) have been granted  Options or SARs under the Plan during the one year period
prior to service on the Committee, except for grants which would not affect such
director's status as "disinterested"  for purposes of Rule 16b-3 (or any similar
rule) of the Securities and Exchange Commission. Except with respect to Retainer
Fee  Options,  the  Committee  may  determine  from time to time which  eligible
participants  shall be granted  Options  or SARs  under the Plan,  the number of
Shares to be subject to the Option in each case, the number and type of SARs, if
any, to be awarded in each case,  and the other  substantive  provisions of each
Option and SAR agreement. However, any Options, other than Retainer Fee Options,
or SARs  granted to a member of the Board must also be approved by a majority of
the Board not including the recipient.

6. Retainer Fee Options.

(a) During each Retainer Fee Year, each Eligible  Director will be granted 4,000
Options in lieu of a cash  Retainer Fee. Such number of Options may be increased
or decreased by the Board from time to time,  but not more often than once every
six months other than to comport with changes in the Internal  Revenue Code, the
Employee  Retirement Income Security Act, or the rules  thereunder.  Such number
will also be subject to adjustment as provided in Paragraph 15 hereof.  One-half
of each year's Retainer Fee Options will be granted on the first business day of
each  Retainer Fee Year and the  remaining  one-half of the year's  Retainer Fee
Options  will be granted on the first  business day that is six months after the
first day of the Retainer Fee Year.

(b) The Committee may determine  from time to time the terms of the Retainer Fee
Options,  provided such terms are consistent with the terms of the Plan.  Unless
otherwise  determined by the Committee,  (i) Retainer Fee Options shall not vest
(and therefore will not be  exercisable)  until one year after the Date of Grant
and (ii) if an  Eligible  Director  ceases  to be a member  of the Board for any
reason,  unvested Retainer Fee Options shall expire and be unexercisable and the
portion  of the  Eligible  Director's  Retainer  Fee  earned  as of the  date of
cessation  that is  represented  by such unvested  Retainer Fee Options shall be
paid in cash.

7.  Eligibility.  Eligible  participants  under the Plan  shall be all  salaried
employees,  consultants  and directors of the Parent  Company or any  Subsidiary
Company.  Only  Eligible  Directors  shall be eligible to receive  Retainer  Fee
Options pursuant to Paragraph 6.

<PAGE>

8. Option Exercise Price.

(a) The price at which Shares may be purchased on exercise of an Option shall be
determined  in each case by the  Committee,  but may not be less than 50% of the
Fair Market Value of the Shares on the Date of Grant;  provided,  however,  that
the price at which  Shares may be purchased on exercise of a Retainer Fee Option
shall be the Fair Market Value of the Shares on the last trading day immediately
preceding the Date of Grant.

(b) Upon  exercise of any Option  granted  pursuant to this Plan,  the  Optionee
shall pay to the Parent Company the full Option price:

(i) By check or in cash; or

(ii) By delivering to the Parent  Company  certificates  for Shares owned by the
Optionee  and  endorsed to the Parent  Company  representing  a number of Shares
having a then current Fair Market Value equal to the Option price; or

(iii) Any combination of the above.

Upon payment of the Option price the appropriate  accounts of the Parent Company
shall then be credited accordingly.

9. Issuance of Certificates; Payment of Cash.

(a) Upon  payment of the Option  price,  a  certificate  for the number of whole
Shares  and a check for the Fair  Market  Value on the Date of  Exercise  of the
fractional  Share,  if any, to which the Optionee is entitled shall be delivered
to such Optionee by the Parent Company,  provided that the Optionee has remitted
to his employer an amount,  determined by such  employer,  sufficient to satisfy
the applicable requirements to withhold federal, state, and local taxes, or made
other  arrangements  with his employer for the  satisfaction of such withholding
requirements.

(b) Upon exercise of SARs, the Value of such SARs shall be paid one-half in cash
and  one-half  in  Shares.  The number of Shares to be  delivered  by the Parent
Company shall be an amount equal to 50% of the Value of such SARs divided by the
Fair Market Value of a Share on the Date of Exercise of such SARs.  Any right to
a  fractional  Share  shall be  satisfied  by the Parent  Company  in cash.  The
employer of the  Optionee or Holder shall deduct from the amount of cash payable
any amount necessary to satisfy applicable federal,  state, or local withholding
requirements.

10. Term. Unless otherwise determined by the Committee,  Options or SARs granted
under the Plan shall not be exercisable after five years from the Date of Grant.

11. Exercise of Options and SARs.  Unless otherwise  determined by the Committee
and subject to the  provisions  of Paragraphs 12 and 14, an Option or SAR may be
exercised  in whole or in part during its term,  provided  that an Option or SAR
shall be  exercisable  only by the Optionee or Holder  during his lifetime  and,
unless otherwise  determined by the Committee and except for vested Retainer Fee
Options,  only while he is a salaried  employee,  consultant  or director of the
Parent Company or of a Subsidiary Company.

<PAGE>

12. Death or Termination of Qualifying Relationship. Unless otherwise determined
by the  Committee,  Options  (other than vested  Retainer  Fee Options) and SARs
shall  terminate  upon the  termination  for any  reason  of the  Optionee's  or
Holder's qualifying relationship with the Company, except that if an Optionee or
Holder dies while holding a vested Option or SAR not fully exercised or expired,
the  unexercised  portion  may be  exercised  by his  estate  or  his  heirs  or
beneficiaries within the period of six months following the date of death (in no
event,  however,  may an Option or SAR be  exercised  after its  stated  date of
expiration).  For purposes of this Plan, a transfer of a participant between two
employers,  each of  which  is a part of the  Company,  shall  not be  deemed  a
termination of employment.

13.  Relationship  Between Options and SARs. Upon exercise of an Option, any SAR
attached to such Option  shall  automatically  expire.  Upon  exercise of an SAR
attached to an Option, the related Option shall automatically  expire. Except as
set forth above,  the grant,  exercise,  termination or expiration of any Option
granted to an Optionee or Holder  shall have no effect upon any SAR held by such
Optionee or Holder, and the grant, exercise, termination or expiration of an SAR
granted to any  Optionee or Holder  shall have no effect upon any Option held by
such Optionee or Holder.

14.  Transferability  of Options and SARs.  No Option or SAR may be  transferred
except by will or the applicable laws of descent and distribution.

15.  Adjustment on Change in  Capitalization.  In case the number of outstanding
Shares  is   changed   as  a  result   of  a  stock   dividend,   stock   split,
recapitalization,  combination, subdivision, issuance of rights or other similar
corporate  change,  the Board shall make an  appropriate  adjustment  in (a) the
aggregate  number of Shares  which  may be  issued  under the Plan,  (b) the per
individual  annual  limitation set forth in Paragraph 3 above, (c) the number of
Retainer Fee Options to be granted each year to Eligible  Directors  pursuant to
Paragraph 6 above, and (d) the number of Shares subject to, and the Option price
or Value of, any then outstanding Options or SARs.

16. Certain Corporate Transactions. If during the term of any Option or SAR, the
Parent  Company  or any of the  Subsidiary  Companies  shall be  merged  into or
consolidated  with or otherwise  combined with or acquired by another  person or
entity,  or there is a  divisive  reorganization  or a  liquidation  or  partial
liquidation  of the Parent  Company,  the Parent  Company  may (but shall not be
required to) take any of the following courses of action:

(a) Not less than 10 days nor more than 60 days  prior to any such  transaction,
all  Optionees  and Holders  shall be notified that their Options and SARs shall
expire  on the 10th  day  after  the date of such  notice,  in which  event  all
Optionees  and Holders shall have the right to exercise all of their Options and
SARs prior to such new expiration date; or

(b) The Parent  Company shall provide in any agreement  with respect to any such
merger,  consolidation,  combination or acquisition  that the surviving,  new or
acquiring  corporation shall grant options and stock appreciation  rights to the
Optionees and Holders to acquire shares, or stock appreciation rights in shares,
in such  corporation  provided  that the excess of the fair market  value of the

<PAGE>

shares of such  corporation  immediately  after the consummation of such merger,
consolidation, combination or acquisition over the option price, or the value of
such stock  appreciation  rights at the time of grant, shall not be greater than
the  excess of the Fair  Market  Value of the Shares  over the  Option  price of
Options,  or  the  Value  of  the  SARs  as  determined  under  Paragraph  2(r),
immediately prior to the consummation of such merger, consolidation, combination
or acquisition; or

(c) The Parent Company shall take such other action as the Board shall determine
to be reasonable under the circumstances in order to permit  Optionees,  Holders
and Eligible  Directors to realize the value of rights granted to them under the
Plan.

17. Plan Not to Affect  Relationship With the Company.  Neither the Plan nor any
Option or SAR shall  confer  upon any  participant  any right to continue in the
service of the Company.

18. Amendment. The Board may at any time terminate the Plan or make such changes
therein as it shall deem  advisable.  The Board may not,  however,  without  the
approval of the voting  shareholders  of the Parent  Company,  (i)  increase the
total number of Shares which may be  delivered  under the Plan,  (ii) change the
class of  persons  eligible  to  receive  Options or SARs,  (iii)  withdraw  the
authority to  administer  the Plan from a committee  consisting  of directors or
(iv)  otherwise  amend the Plan in a manner which would  require the approval of
the  shareholders  of the Parent  Company  in order to  maintain  the  exemption
available  under Rule 16b-3 (or any similar rule) of the Securities and Exchange
Commission. No outstanding Option or SAR shall be affected by any such amendment
without  the  written  consent  of the  Optionee,  Holder or other  person  then
entitled to exercise such Option or SAR.

19.  Securities Laws. The Committee shall make each grant under the Plan subject
to such  conditions  as shall cause both the grant and exercise of any Option or
SAR to comply with the then-existing  requirements of Rule 16b-3 (or any similar
rule) of the Securities and Exchange Commission.

     Unless otherwise permitted by the Committee, the date of any exercise of an
SAR by a Holder or an Optionee who is an officer,  director or beneficial  owner
of ten  percent or more of any class of any  registered  equity  security of the
Parent  Company shall be required to occur within the period  beginning with the
third and ending with the twelfth  business day after the date of the release of
the Parent Company's  quarterly or annual sales and earnings  information to the
public.

20. Performance-Based  Compensation.  Unless otherwise provided by the Committee
in their  discretion  pursuant to the first  sentence of Paragraph  8(a),  it is
intended that all compensation  income  recognized by employees as the result of
the  exercise  of Options or SARs,  or the  disposition  of Shares  acquired  on
exercise of Options or SARs, shall be considered performance-based  compensation
excludable from such employee's  "applicable employee  remuneration" pursuant to
section 162(m)(4)(C) of the Internal Revenue Code of 1986, as amended.

21.  General.  Each  Option  or SAR  granted  shall be  evidenced  by a  written
instrument  containing such terms and conditions not inconsistent  with the Plan
as the  Committee  may  determine.  The issuance of Shares on the exercise of an
Option or SAR shall be  subject  to all of the  applicable  requirements  of the
Pennsylvania  Business  Corporation Law and other  applicable  laws. Among other
things  the  Optionee  or  Holder  may be  required  to  deliver  an  investment
representation  to the Company in  connection  with any exercise of an Option or
SAR or to agree to refrain  from  selling or  otherwise  disposing of the Shares
acquired for a specified period of time.