Institutional and individual determinants of adult participation in higher education are examined. By means of an ordinary least squares regression, the 1970 degree-credit college enrollment of a sample of 57,689 married men and women 25 or older living in metropolitan areas was predicted. Being a Vietnam veteran tripled the likelihood of a male's attending college. Establishing a new two-year college where none had existed before or lowering the tuition from $400 to zero doubled the college attendance rate of local adults. None of the characteristics of local four-year public colleges was found to have a significant effect on adult college attendance. (Author)