This excerpt taken from the IBM DEF 14A filed Mar 10, 2008.
5. Compensation Committee Consultant
The Committee currently retains a Managing Director of Towers Perrin as its outside compensation consultant to advise the Committee on market practices and the specific IBM policies and programs. This Managing Director does not perform any work for the Company. The consultants work for the Committee includes data analyses, market assessments, and preparation of related reports. The work done by Towers Perrin for the Committee is documented in a formal scope of work and contract which is executed by the consultant and the Committee.