INTRODUCTION

One of the major challenges facing the field of substance abuse treatment is the coordination of community-based services for clients with cooccurring mental or physical health disorders (1). Given their multiple health needs, these clients often are required to participate in two or more specialized programs that involve providers in areas such as mental health and primary care. As a result of this specialization, many policymakers and researchers have raised the concern that the substance abuse treatment system may be too fragmented to deliver effective care (2, 3).

The fragmentation of community-based substance abuse treatment became an issue in the 1980s when the plight of persons disabled with serious cooccurring disorders was recognized as a burgeoning social problem (4). The issue has intensified in recent years as managed care has assumed a stronger presence in behavioral health care and as an increasing numbers of persons with substance abuse, mental illness, and chronic health problems such as HIV/AIDS have begun to be treated in outpatient settings (1). Treatment of these multineed persons constitutes a major frustration among outpatient substance abuse treatment providers because many of these persons are revolving door clients who enter treatment, often discontinue early, relapse, and recycle anew (1). Some researchers have suggested that in order to reduce recidivism among these substance abuse clients, multiple types of treatment must be provided concurrently through better linkage of care between outpatient substance abuse treatment agencies (OSATs) and other service providers (1, 5-9).

Indeed, empirical evidence supports the effectiveness of concurrent treatment. Joe and colleagues (10) showed that methadone clients had less relapse to opiate use when they received ancillary services, particularly mental health care. McLellan and associates (11) found similar results in a study of 649 opiate, alcohol, and cocaine patients. An evaluation of a combined substance abuse and mental health case management program also found a 31% reduction in the number of days homeless for dually diagnosed persons as compared to 6% in a typical service control group (12). More recently, Jerrell, Wilson, and Hiller (13) showed in a demonstration project that clients receiving services through a well-implemented dual disorder treatment program functioned better in the community than clients not receiving services from such a program.