This paper describes the results of a collaboration between three local community colleges in Oregon, Clackamas Community College, Portland Community College, and Mount Hood Community College with Portland State University, to study student transfers among the institutions. Using a random sample of 504 students who had completed at least three credits during the academic year 1990-91, but did not enroll at the same college in the following year, the study examined student flow patterns, efficiency of the transfer process in terms of credit-hour loss, and academic performance patterns, focusing primarily on students' behavior and on the collective role of the four institutions in delivering postsecondary education. The study found the pattern of student movement between community colleges and the university to be complex, with students appearing to use the public institutions as a system rather than as four separate entities. The study also found very little of the credit losses experienced by transfer students to be the result of poor articulation between the institutions, but rather due to reasons such as advising problems, poor communication between institutions, or student choice to improve performance records. (Contains 13 references.) (CH)