Hours of work equations are derived from the constrained maximization of a utility function that is not separable over time and that varies with a household's demographic structure. these equations are fitted to observations on wage rates, nonlabor income, and other variables for husbands, wives, and unmarried women. The dependence of each household's current work and consumption behavior upon its work and consumption behavior in the past is examined closely and different interpretations of the relationship are confronted with the data.