This study aims to advance understanding of service provision to the homeless population through investigation of the effects of organizational characteristics. A longitudinal study of homelessness obtained structured psychiatric interview data from 400 participants and these individuals' service use and organizational data from 23 organizations over the next 12 months. Substance abuse service use was associated with organizational funding diversity, professionalism, and focus of services on substance abuse service provision. Other mental health service use was associated with small organizational size, professionalism, and simplicity of organizational funding diversity. Shelter service use was associated with complexity of services and small organizational size and inversely related to professionalism of staff. Results suggest relevance of organizational characteristics to understanding service access and use, controlling for individual need factors. Only by examining interactions among individual and organizational characteristics across sectors of care can the complexity of service provision to this multifaceted population be approached.
