We report on the transverse compression testing of fine,highly anisotropic polymer fibers. Single KEVLAR 29 fibers were laid on a flat, stiff platen, and compressed by a second, stiff, parallel platen. Test output was a force-deflection curve, from which the effective transverse modulus, apparent strain at yield and the work required to compress the fibers were determined. The effects of specimen aspect ratio was examined experimentally and by finite element simulation for loaded fiber lengths of 1/4 to 7 fiber diameters, and a method proposed to deduce the plane strain response from short aspect ratio tests.