This paper summarizes the features of the City University of New York's (CUNY) open admissions plan and briefly describes its accompanying research component. Its major features are: (1) a system of 4 and 2 year colleges, with students eligible for the 4-year institutions if their high school average is 80 or better or if they rank in the top half of their class; (2) a system of university-wide testing to avoid the high attrition rates of many open door policies; and (3) the development of a large scale program of supportive services. Research on the program is being conducted by the American Council on Education (ACE) and CUNY. ACE has collected data on numerous variables pertaining to student socioeconomic and demographic characteristics, as well as attitudinal information derived from questionnaires and interviews. Interviews have also been conducted with administrators and some faculty to assess the different ways in which each campus has implemented open admissions. The research will focus on: (1) characteristics of support services most closely associated with attrition rates; (2) components of remedial programs that have the greatest impact on improving skills; and (3) attitudinal and performance changes over the first year. CUNY plans to continue to expand this work, but is facing financial and administrative problems in carrying it out. (AF)