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EX-10.13

     Letter Agreement dated February 27, 2000 between the Registrant and Barry
S. Cain

                                                                   Exhibit 10.13


February 27, 2000


Mr. Barry S. Cain
755 Smoke Tree Road
Deerfield, IL 60015

Dear Barry:


This letter will confirm our recent conversation regarding the terms of your
resignation from Navigant Consulting.

 .    We agreed that your last day of work was February 18, 2000, that you have
     resigned effective August 18, 2000 (the interim period being the "Notice
     Period") and that during such Notice Period your sole responsibility will
     be to endeavor to secure employment outside the Company.

 .    During the Notice Period, the Company has agreed to continue to pay you
     your regular salary, payable per our normal executive payroll cycle;
     provided, however, that the last three months' take-home salary (i.e., net
     of withholding for taxes, benefits etc.) will not be paid directly to you
     but instead will be applied as a credit to reduce the interest on your
     loans from the Company. No severance pay shall be due you at the end of the
     Notice Period.

 .    During the Notice Period, all regular executive employee benefits in which
     you are eligible to participate (e.g., life, disability, medical and dental
     insurance; 401(k)) will continue, but there shall be no further vacation
     accrual. Eligibility for COBRA benefits will commence at the end of the
     Notice Period.

The above terms are contingent upon your agreement to full and complete
cooperation with the Company's outside counsel in relation to outstanding
litigation matters. To avoid any possible misunderstanding, "full and complete
cooperation" means that no later than March 3, 2000, you will submit yourself to
an interview by the Company's outside counsel, you will be candid and
forthcoming, you provide to them all requested documents in your possession, and
you will thereafter make yourself available during the Notice Period to the
Company or its representatives, upon reasonable notice, and
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cooperatively provide requested information or documents. Regardless of whether
such interviews take place before or after your last day of work, the Company
will treat the contents of the interview as a privileged Company communication
between an employee and counsel representing the Company for purposes of
defending the pending class actions. You shall be entitled at all times to
advice and counsel from your own attorney.

We have also agreed on the following

 .    As soon as reasonably possible, the Company shall -

     -  pay you for your 7 weeks' of accrued unpaid vacation pay, and

     -  provide you with a mutually agreeable letter of recommendation.

 .    During the Notice Period, office voice mail will continue to be available
     at the same extension to the extent possible, together with telephone
     answering as necessary.

 .    You may retain your computer, but you must allow us to create a backup copy
     of all business-related files on your computer as soon as mutually
     convenient.

As an interim matter, I asked Phil Steptoe to assume your various
responsibilities following February 18, 2000. Please cooperate with him to the
extent he reasonably requires your knowledge of past matters.

If you agree that this letter accurately reflects the agreement between you and
the Company, please countersign this letter and return it to me.

Best regards,


M.H. Saranow
Chairman

                                                       Agreed and Accepted:

                                                       --------------------
                                                       Barry S. Cain

                                                       Dated:

                                                       --------------------