The sex differential in mortality from all causes and ischemic heart disease is examined in an upper-middle class Caucasian community of 3516 adults in southern California, who were followed for a minimum of seven years. The influence of several demographic, behavioral, and biologic risk factors is simultaneously controlled for by means of a multiple logistic analysis. Risk factors include age, marital status, education, cigarette smoking, cholesterol, systolic blood pressure, fasting plasma glucose, and obesity. Both the prevalence and relative mortality risk associated with several risk factors differ by sex. Adjustment decreases the sex differential for mortality from 1.7 to 1.3 for all causes and from 4.8 to 2.4 for ischemic heart disease. When analysis is limited to healthy men and women, the adjusted sex differential in mortality is 1.2 for all causes and 2.0 for ischemic heart disease. Findings of this study are compared with two other population-based studies.