Among the freshmen who entered the City University of New York (CUNY) in fall 1970, about 63% were enrolled without interruption in each of their initial four semesters. Approximately 70% of them were enrolled in CUNY during spring 1972, the fourth semester since their original enrollment. At the senior college, more than 75% were in attendance during the fourth semester; this was true for 60% of the students from the community colleges. At both, high school average was positively associated with retention. Among students who left college, about 18% returned and were present for the fourth semester. While attrited students from community colleges were more likely to return than those from senior colleges, the differences were quite small. With regard to net retention rates, there was considerable variation among the colleges of CUNY. There was even more variation in the rates of return of attrited students. When the CUNY net retention data over four semesters are compared with national data over eight semesters, it is apparent that considerably more attrition will have to occur before the CUNY net retention rate approaches the threshold defined by the national data. (Author)