Cooperative education can enhance classroom instruction by providing practical work experience that is relevant to students' career goals. Among co-op's benefits to students are increased relevance of learning and motivation for study; improved self-reliance, self-confidence, and responsibility; contacts with potential employers; and higher starting salary after graduation. Among the benefits to participating institutions are improved relationships with business and the community; enhanced student retention and graduate placement; workplace-tested curriculum; and less need to maintain expensive state-of-the-art facilities. Among the benefits to employers are effective screening and recruitment; higher employee retention and productivity; and improved public relations. Co-op education appears to work best in metropolitan settings, in community colleges, and for students who major in engineering, business, and health occupations. However, fewer than 2 percent of all full-time postsecondary students and no more than 10 percent of all secondary vocational education students are involved in co-op programs. Some research on the effects of co-op education has been criticized for methodological weaknesses. Among the suggestions for increasing co-op's impact are to recruit larger numbers of the students most likely to benefit from it and to promote co-op as a viable alternative to heavy borrowing for college expenses. (Eleven references are included.) (CML)