The concept of quality of life currently impacts program development, service delivery, management strategies, and outcome evaluation in the area of intellectual disabilities. Maryland uses peer interviewers to assess consumer-perceived quality of life among adult recipients of MR/DD services and supports. In this article we describe the survey instrument and procedures and discuss assessment issues of quality of responses, acquiescence, and proxy respondents. We present the psychometric properties for eight core quality of life domains among 923 people assessed in FY 2001. Results are summarized and development of a model for enhancing social inclusion, personal development, and self-determination was described. Service and personal characteristics relating to quality of life as well as some ways the results can be used for program enhancement are discussed.