This volume examines a number of facets of the labor market experience and behavior of middle-aged men. It is based on a unique set of longitudinal data collected by personal interviews among the same sample of men in 1966, 1967, 1969, and 1971. The data contain a complete record of the labor market activity of the men over a five-year period, allowing a look at both the antecedents and consequences of particular events and courses of action. The papers in this volume do not purport to analyze all of the aspects of the labor market experience of middle-aged men, but rather focus on particular problems or aspects of behavior that have significant bearing on the welfare of this group of men. The chapter headings include: (1) Earnings and Employment of Middle-aged Men--A Special Study of their Investment in Human Capital; (2) Middle-aged Job Changers; (3) Occupational Mobility among Middle-aged Men; (4) Early Retirement; and (5) Internal-external Control and Labor Market Experience. (Author/PC)