Based on the resuLts from previous studies, different cotton (Gossypium) genotypes and species were chosen to be implemented into a program for developing resistance to the reniform nematode, Rotylenchulus reniformis. Different techniques for determining resistance to the reniform nematode were used. Visual examination and rating of cotton roots was not as effective in determining resistance as evaluating nematode egg production. This research focuses on our efforts to examine previously reported sources of resistance.