This paper presents a portion of the work done by the authors in developing a new approach to evaluation techniques for wear of solid film lubricants. The theory and experimental requirements are presented that are necessary to adapt the use of “wear coefficient” to the extremely thin films required for these materials. A method for correlation of wear data obtained on various testers is included. Experimental results have covered an environmental temperature range from —320F to 1100F. Design formulas for linear motion, journal, thrust, and spherical bearings have been derived to utilize experimental data in the estimation of hardware bearing wear.Presented at the 22nd Annual Meeting of the American Society of Lubrication Engineers held in Toronto, May 1–4, 1967.