A study of 60 adults, ages 23-38, was done to assess the fit of life-stages (periods during which adults of similar age face common problems, events, pressures, situations) identified by writers in adult development for these ages. Focus was on (1) creating a structured interview schedule to obtain data which should be age-related and (2) creating a system by which judges were trained to identify life-stages and to apply that identification scheme. The life-stages included for study were (1) Leaving the Family (late teens-early twenties), (2) Provisional Adulthood (early twenties-late twenties), (3) Age 30 Transition (late twenties-early thirties), (4) Settling Down (early thirties-late thirties) and (5) Mid-Life Transition (late thirties-early forties). Twenty middle-class individuals (9 men and 11 women) from each of three age groups, 23-27, 29-32, 34-38, were interviewed in taped sessions designed to elicit in-depth responses regarding occupation, leisure, and relationships. Evaluating the presence or absence of various characteristics, two raters for each interview distributed 100 percentage points among scales representing the life-stages. Interrater correlations, means and standard deviations of the life-stage ratings by age group, and analysis of variance of group differences were computed. It was concluded that with training in life-stages descriptions, individuals can classify subjects into life stages with reasonable accuracy. The results suggest that life-stages do not fit completely for the individuals studied, with the fit being poorest at Age 30 Transition, but that life-stages are reliably associated with differences between age groups. (EM)