In the area of chronic ambulatory illness, it is well recognized that poor participation by patients in the treatment process greatly limits the potential benefits of effective medical technology. Patients' contributions to treatment outcomes might be enhanced if medical care was oriented to consider patients as active participants in the treatment process, rather than as passive-obedient recipients of care. A systematic attempt is needed to define and measure services along a specific dimension of “Active Patient Orientation” and to relate these measurements directly to treatment outcomes. Applying a socio-organizational perspective, the study reported here examined the link between an active patient orientation and treatment outcomes. Hypertensive patients were asked to characterize their care along the dimension of Active Patient Orientation (APO). Findings indicate that patients who are afforded a high degree of APO are significantly more likely to have their blood pressures under control and to exhibit more positive cognitive and behavioral responses to illness-management. Further, the data suggest that level of APO can be significantly increased through incremental changes in systems of routine clinic care.