The way students move through a community college once they have enrolled has crucial implications for policy-making and administration, but has been given inadequate attention by researchers. A model of student flow is described in terms of progress toward graduation, based on records of sources of students, freshmen and sophomore flows, and graduation patterns over five years. Over this period the percent increase in the number of graduations was greater than the percent increase in the number of sophomores, while the percent increase in the number of sophomores was greater than the percent increase in the number of freshmen. Students continuing college work increased in the "pipeline" at three times the rate of first-time collegians. An application of the model to the class of 1970 revealed that three times as many students went "straight through" as those who were "in and out," 60 percent of the "stop-outs" interrupted their studies for only one semester, and only one student out of four tried college briefly and dropped out. The evidence also suggests that as many students transferred before graduation as graduated. (Author/BB)