The inmate socialization theory contends that an inmate's perceptions and behaviors are attributable to the socialization process within the institution, whereas the importation theory argues that adaptations made and perceptions acquired prior to institutionalization are the primary influences. This study administered the CIES and the SDS on two occasions, once early in an inmate's stay and another after several weeks of residency, to measure the amount of convergency to institutional norms over time with increased exposure to those norms. Subjects were 118 male residents of three halfway houses operated by the Magdala Foundation in St. Louis, divided equally into an experimental group and a control group whose members did not take the tests until they had spent 3 weeks in the program. Institutional norms were derived from the control group. Participants were at least 18 years old, had an average IQ of 103, and a mean grade level achieved of 10.4, 66 percent were black, 32 percent were white and 2 percent Oriental. Of the group, 78 were classified as postincarcerative because they had spent a minimum of 180 days in the penitentiary immediately before entering the halfway houses and 40 were preincarcerative, having served less than 180 days or no time in a penitentiary. Primary analysis indicated a trend in the direction of movement to institutional norms, supporting the socialization view. However, a detailed inspection of the individual subscales showed that the preincarcerative and postincarcerative groups approached the institutional norms differentially, offering some support for the importation position. Thus, the results support an interactive model involving both perspectives. The article includes tables and 25 references.