The burden of care experienced by family members of 90 patients with major affective disorder was evaluated. The extent of burden in these families was considerable. The burden was significantly more among families of bipolar patients than those of major depression. Prolonged illness and high levels of dysfunction among patients correlated consistently with severity of burden. Severity of illness, higher age of the patient and number of episodes of the illness also influenced the extent of burden. Variables such as gender of the patient, religion, education, occupation, family type and size and the locus of control of both patients and relatives did not influence the extent of burden significantly. These results have substantial implications for the planning of intervention strategies.