Assuming that the holding power of a junior college is one of the significant indices of its effectiveness, this paper reviews descriptive and inferential data on student attrition. Included are dropout statistics, reported reasons for leaving college, and personality characteristics of dropouts versus persisters. Comparisons between numbers of dropouts at junior and 4-year, public and private, large and small, and co-ed and single sex colleges were made. The conclusion is that small enrollment schools (250-750), whether 2- or 4-year, enjoy higher retention rates. The personality profiles of dropouts reported in the literature surveyed here are not consistent, although it is generally believed that high dropout rates in junior colleges are primarily attributable to the lower level of motivation and poorer academic preparation of students. The value of special programs for potential dropouts and types of college environments which seem to foster higher dropout rates are also discussed. (LP)