Objective: To determine whether employment outcomes of people with disabilities can be predicted by the social-cognitive/attribution theory of stigmatization. Design: Ex post facto design using data mining technique and logistic regression analysis. Participants: Data from 40,585 vocational rehabilitation (VR) consumers were extracted from the Rehabilitation Services Administration Case Services Report (Form 911). Results: In Study 1, data mining results revealed that the most significant predictor of employment outcome was type of disability. Consistent with the social-cognitive/attribution theory of stigmatization, the employment rate of people with physical disabilities (68.5%) was found to be significantly higher than that of people with mental disabilities (56.6%). In Study 2, results from logistic regression analyses indicated that VR services could improve outcomes for subpopulations of people with disabilities with low employment rates. Conclusion: Employment outcomes of VR consumers were found to match the hierarchy of attitudes toward disability predicted by the social-cognitive/attribution theory. However, even with subpopulations with the lowest employment rates, VR services were found to improve employment outcomes. (Contains 2 tables and 2 figures.)