Mental health professionals have long speculated that the physical environment in which treatment occurs has an impact on both the treatment process and its outcome. The few empirical studies that evaluated the effects of psychoenvironmental design have shown encouraging results and demonstrated clinically desirable behavioral changes and even reduced psychopathology. In view of the concept that architecture is a tool in the therapeutic process, the design and execution of the psychiatric hospital in the Chaim Sheba Medical Center at Tel-Hashomer, Israel, were conducted by a multidisciplinary team of architects, mental health professionals, and administrators. The hospital contains three acute inpatient wards and a day care and large outpatient clinic. Its operation began in 1991. This paper deals with the merging of "user-friendly" architectural and environmental design components that create an integral healing environment. The paper discusses the positive effects of specific components on patients and staff, and suggests that our model of psychoenvironmental approach to psychiatric hospital design can provide an important and effective tool in the pursuit of a humane, efficient containment and reduction of severe psychopathology.