Most youth in transition services with labels of intellectual and developmental disabilities (IDD) have poorer employment outcomes than their peers with other or without disabilities. One alternative approach to address this challenge provides youth with IDD access to transition services in the context of a college or university campus. College-based transition services (CBTS) provide students with IDD access to college courses, internships, and employment during their final 2 to 3 years of secondary education. A quasi-experimental design evaluation of one college-based transition services model, Think College Transition, found that, after controlling for student baseline scores, the college-based transition services had a significant effect on students' scores of self-determination at post-test. Implications for further refining the model are discussed.