Economic loss and hardship during the 1929 Depression produced marital tension resulting from increased conflict over finances and temperamental behavior of husbands and wives. Data on 110 couples were obtained from the Berkeley Study at the Institute of Human Development in California. Annual data were collected from wife, home observer, and child from 1929 to the end of World War II. Husbands were interviewed in 1930 and again in the early 1940s. Differential loss of income during this period formed the focus of this study. Marital tension and temperamental (irritable, emotionally unstable, tense) scales were developed by trained coders who used original qualitative data. Heavy income loss during the 1930s increased financial disputes which substantially raised the level of tension in marriages and which weakened marital relations by increasing temperamental behavior, particularly of men, who, as major breadwinners, became worrisome, unstable, and explosive. Both effects were most pronounced among families with minimal psychological coping resources, initially weak marriages, and unstable men. Couples of higher socio-economic status were more affected by Depression losses than couples in the working class. (KC)