OFFER OF EMPLOYMENT

Exhibit 10.b

[CDI Letterhead]

August 26, 2005

Mark A. Kerschner

537 James Street

Morristown, NJ 07960

Dear Mark:

I am pleased to confirm our offer of employment, pending finalization of background and reference checks, as Chief Financial Officer for CDI Corporation, reporting to me. Your first day of employment will be on or before September 22, 2005. Please report to 1717 Arch Street, 35 ^th Floor, Philadelphia, PA.

Your bi-weekly base salary will be $11,923.08. If expressed on an annualized basis, your salary would be equivalent to $310,000.00. Contingent upon Company performance, you will be eligible for a target bonus for calendar year 2005 of 50% of your annual base salary, pro-rated from your date of hire; for 2005 only, the minimum bonus payment will be $30,000.00 assuming you remain employed with the Company throughout 2005. Additionally, you will be eligible to receive 10,000 stock settled stock appreciation rights, 2,500 shares of time vested deferred stock and 5,000 shares of performance contingent deferred stock subject to the terms and conditions of the 2004 Omnibus Stock Plan. The exercise price will be the closing price of CDI’s stock on your start date.

You will be eligible to participate in CDI’s Custom Choice Employee Benefits Program, which is outlined in the benefits information being mailed to you under separate cover. A summary of benefits is included herein. If you do not receive a benefits enrollment packet at your home within three weeks of your hire date, please contact the CDI Benefits Hotline at (800) 763-8050.

In connection with relocation to Philadelphia, you will be entitled to the provisions of the CDI Relocation Policy (included herein). In order to maintain the continuity of your relocation benefit, all real estate contacts must be made through Beth Bolen at FAS Relocation Network. Beth can be reached at 800-522-1052. Van line contracts must be made through CDI-approved vendors.

For each share of CDI Common Stock that you purchase – up to 20,000 shares – within a specified fifteen day period following the start of your employment, the Company will grant you 0.4 shares of time-vested deferred stock which will vest at the rate of 20% per year over five years, so long as you retain all of the shares purchased. If at any time during the five years you sell or transfer any of the 20,000 shares, then the remaining unvested shares of your Deferred Stock will be forfeited. Your ability to sell the shares will be subject to CDI’s ownership and holding requirements.

Please note that CDI Corporation reserves the right to amend or terminate benefits and incentive plans in accordance with the terms of those plans.

You will receive copies of CDI’s core HR policies at the outset of your employment with the Company. At that time, you will be required, as a condition of employment, to certify in writing that you agree to abide by all CDI policies.

In keeping with our “drug free workplace” policy, this offer of employment is contingent upon the successful completion of a urine drug test at a CDI-approved testing facility within 48 hours of your receipt of this letter. You, therefore, should not make any irreversible plans until this contingency is satisfied. Enclosed is the form that you will need to complete the drug test.

Your employment status with CDI will be “employment-at-will,” which means there is no guarantee of employment for any specified period of time and both the employee and/or CDI can terminate the employment relationship at any time, with or without cause. This “employment-at-will” status cannot be changed except in a written employment agreement signed by you and an authorized representative of CDI.

Mark, my staff and I look forward to having you join the CDI team. Please acknowledge your acceptance of this offer in the space provided below and sign the accompanying Employment Agreement documents. Return a copy of each for our records. Also sign and return the blue “Relocation Expense Reimbursement Agreement Appendix I” to commence the relocation process.

EMPLOYMENT AGREEMENT

General Information

Employer:  CDI Corporation

Employee:  Mark A. Kerschner

Employee Address: 537 James Street, Morristown, NJ 07960

Effective Date of Agreement: on or before September 22, 2005

Terms and Conditions

Throughout this Agreement, the Employer will be referred to as “we”, “us” or “our” and the Employee will be referred to as “you” or “your”. The above General Information, these Terms and Conditions, the compensation agreed upon between you and us (which is presumed to be the compensation we pay you), those benefits for which you are eligible under our benefit programs (as they may be modified from time to time) and any schedules or attachments, together make up the Employee’s Employment Agreement (“Agreement”).

1. Services to be Rendered . As our Employee, you agree to use your best efforts to perform those services for us as we may direct and to supervise and direct all personnel employed by us who are under your control. You agree that you will not during the term of this Agreement, directly or indirectly, render any services of a business, commercial or professional nature to any other person or organization, whether for compensation or otherwise, without our prior written consent.

2. Company Policies . You agree to abide by and comply with all of our practices and policies.

3. Confidentiality and Property Rights .

(a) You acknowledge that in the course of your employment by us you will have access to and be exposed to valuable confidential and trade secret information of ours and our customers. You agree, during the term of your employment and forever thereafter, to keep confidential all information and material of ours or our customers (“Confidential Information”) that relates to our or our customers’ business, employees, customers, vendors or other parties we do business with and excluding only information that is or becomes public knowledge through no fault or participation by you or information which we no longer treat as confidential. You agree to keep in strictest confidence and not to disclose, use, copy or make available to others any Confidential Information except as is required in the course of your performing services hereunder or with our prior written permission. Nothing contained in this Section 3(a) shall be construed to restrict your right to discuss your working conditions with others.

(b) All documents, manuals, bids, contracts, financial data, customer lists and information, employee and applicant lists and information, systems for recruitment and sales, equipment, hardware, software, source code, data bases, designs, drawings, plans, data and the like (including all copies thereof), relating to our business or our customers’ business, which you use, prepare or come into contact with, will remain our or our customers’ exclusive property and must be returned to us promptly upon our request or upon termination of your employment with us for any reason.

(c) You agree that all work product, inventions, innovations, concepts, developments, designs, processes, procedures and improvements (“Inventions”) which are made or conceived by you, under your direction or by you jointly with others during the course of your employment with us or within six months after the termination of your employment with us (including Inventions created outside of working hours), whether or not patentable or copyrightable, will be work made for hire and our sole property if related to our business or if created using our resources. You also agree that any copyrights and other proprietary interests in such Inventions will belong to us, and you will promptly and completely disclose and assign all those Inventions to us. You agree that, from time to time as we may request, you will sign all documents and do all other things which may be necessary to secure or establish our ownership of such Inventions and we will reimburse you for the actual and reasonable expenses you incur in this regard. Your knowledge base, experience, expertise and skillsets will belong exclusively to you and are excluded from this Agreement. Any of your Inventions which were recorded or written by you before entering into this Agreement are also excluded from this Agreement and shall belong to you provided that you do not incorporate any such Inventions into any work product created for us.

(d) The provisions of this Section 3 are for our benefit and we will have all rights and remedies to enforce such provisions. Where a provision grants rights alternatively to us or our customers, we shall determine in our sole discretion, the appropriate allocation of such rights.

4. Restrictive Covenants . You acknowledge that, as part of our management team, you will be put in a position of trust and confidence and have access to Confidential Information, including information about our operations and employees, you will be in contact with customers and prospective customers, you will participate in the preparation and submission of bids and proposals to customers and prospective customers, and you will have a role in the formulation and implementation of our strategic plans. Accordingly, for good and valuable consideration, the adequacy of which is hereby acknowledged by you, you specifically agree that it is both reasonable and essential for the protection of our business interests that you agree to the restrictions set forth in Section 5 and Section 6 below.

5. Restrictions Against Post-Employment Solicitation .

(a) If your employment is terminated for any reason, including resignation by you or termination by us, with or without Cause (see Section 8(a) below) , then for a period of one (1) year immediately following the termination of your employment, you agree that you will not, on your own or on behalf of or in connection with anyone else:

(i) directly or indirectly solicit, interfere with or attempt to entice away from us, any emplo