Scientists have investigated nematode populations parasitizing cotton for more than 50 years. The importance of the root-knot nematode-Fusarium wilt complex was recognized early and subsequently has been the target of extensive research. Rotylenchulus reniformis and Belonolaimus longicaudatus also accentuate Fusarium wilt as well as predispose resistant varieties to this disease. Pratylenchus, Hoplolaimus, Helicotylenchus, spp. and other taxa were found to parasitize cotton roots but have little effect on yields or the incidence of wilt. Beginning in the late 1940's, availability of nematicides greatly facilitated the study of these interactions and subsequent crop losses. Although many potential nematicides have been evaluated, the most effective arid consistent were the fumigants D-D, EDB and DBCP. The latter two materials have been suspended by EPA, and D-D has been withdrawn by Shell Chemical Corporation. Those remaining, mostly nonfumigants, provide fair nematode control. Emphasis in the future will probably center around management of nematodes through the use of more effective and safer nematicides, resistant cultivars, crop rotation, and other cultural practices.