The New York WORKS demonstration project was designed to improve employment outcomes for persons with psychiatric disabilities receiving Supplemental Security Income (SSI) disability payments. This article shows how the individual characteristics of participants were related to outcomes at each stage of the multistage recruitment process used in the project and how those characteristics contributed to enrollment. The findings are important to program administrators who are interested in ensuring that SSI recipients receive equal access to employment-related services and who want to improve recruitment strategies for future demonstration projects. The New York WORKS recruitment process used administrative records from the Social Security Administration (SSA) to identify the population of over 68,000 SSI recipients with a diagnosis of a psychiatric disability in Erie County and New York City. Staff involved in the project documented the results of each stage of the recruitment process. The New York WORKS project included four stages: (1) the provision of information (sending a letter and information packet); (2) demonstrated awareness of the project (response to a letter containing an overview of the project); (3) expression of interest (indication of interest in the project, using a postmarked form returned to New York WORKS project staff); and (4) participation (actual enrollment in the program). The project staff members were also able to identify data from administrative records that described the characteristics of the population, including age, sex, type of psychiatric diagnosis, the number of months that the person collected benefits before the recruitment process, employment experience before the recruitment process, and annual earnings in the year before the recruitment process. The data on outcomes at each stage of the recruitment process and the characteristics of SSI recipients were analyzed using an empirical method recently suggested by Heckman and Smith. The analysis identified the relationship between the characteristics of SSI recipients and the outcomes at each stage of the recruitment process and demonstrated how those characteristics contributed to the overall likelihood of enrollment. Demographic characteristics, information about diagnosis, and characteristics related to work history had different effects on outcomes at different stages of the recruitment process. For example, younger SSI recipients were less likely to reply to the information letter but more likely to express an interest in the project and more likely to enroll, given that interest. This result suggests that there may be an information barrier for the younger group of SSI recipients during the early recruitment stages. There were also interesting differences by psychiatric diagnosis and by recent employment experience at each stage of the process. Most notably, persons with anxiety disorders were less likely to express an interest in the project and less likely to enroll in the project if they expressed an interest. This finding suggests that project administrators may need to examine more effective methods to accommodate persons with an anxiety disorder at the enrollment stage of the recruitment process. Persons with relatively low earnings in the year before the project were more likely to respond, to express interest in the project, and to enroll than were those with no earnings and those with relatively high earnings. This finding suggests that the recruitment strategy used by the New York WORKS project is more effective at enrolling a subset of the population that has some demonstrated work capacity and that, of those with a demonstrated work capacity, New York WORKS is enrolling those who are likely to have the most to gain from the project. This finding has implications for the development of sample designs for other demonstration projects, in particular the SSA-proposed mental health treatment study. A number of strategies may lead to improvements in future evaluations of participation in SSA projects and programs. For example, the New York WORKS data did not contain information for all SSI recipients on race, education, or literacy. These factors have been shown to be important in the Job Training Partnership Act literature and are likely to play a role in participation. The inclusion of these data in future evaluations may provide important information on participation in SSA projects. Another useful strategy for future evaluations includes the identification of random samples of those who choose not to enroll at different stages in the process and the collection of information on the reason for the decision. These additional data may help project administrators to gain a clearer description of the reasons for differences in outcome that occur at each stage of the process, assess the overall performance of the recruitment process, and improve the recruitment processes used in future projects.