Student affairs professionals have recognized the importance of physical environment to students' total development and have implemented strategies to enhance the territorial behavior of dormitory residents. However, little research has been done to assess the effectiveness of residence hall personalization programs which allow students to paint and decorate their rooms. A survey of 159 colleges and universities revealed that although most colleges had done no formal evaluation, 38% indicated that damage to public areas had decreased and 62% indicated that their retention rate had increased or remained the same. Fifty percent noted an increased cohesiveness among residents on floors with personalization programs. Personalization of the residence hall was equally accepted by both sexes in all dormitories. In general, the more freedom students had in personalizing their space, the higher their level of territorial behavior. The findings suggest that more and improved assessment techniques are needed to understand the impact of residence hall personalization programs. (JAC)