To test the hypothesis, the dropout rate of nonparticipants with prior propensities to drop out. A California subsample from the 1980 and 1982 High School and Beyond survey -- nearly 3,000 high school sophomores and 3,000 seniors -- were asked to respond to a questionnaires on the dropout-preventing effects of alternatives. The subjects -- black, white, and Hispanic male and female students -- also were surveyed on the labor market outcomes of participation in alternative high school programs. Results on the dropout-preventing affects of vocational education and alternative high school programs indicate that the assessment varies across different procedures used to control for prior propensity to dropout. Findings for labor market effects indicate that participants in vocational and other alternative programs generally have higher employment rates and, for some, higher wages. Tabular data and 17 references.