It is surprising and intriguing to discover that although clinical psychology is widely practiced within psychiatric inpatient settings, little professional literature has been published on this subject and as yet no textbook dedicated to this topic. This introductory chapter will begin with a brief historical survey describing the development of clinical psychology practice within the psychiatric inpatient setting and will introduce the four domains that define clinical psychologists’ work in these settings: 1. Systemic multi-modal and multi-level interventions psychologists perform in the hospital and ward with staff and patients. 2. Psychotherapeutic work with inpatients. 3. Psychodiagnostic assessments and consultations. 4. Clinical training and supervision. Following that, issues and challenges facing clinical psychologists in implementing such work within the psychiatric inpatient system and ward will be described and discussed, ending with an attempt at addressing the puzzling discrepancy between the important value and contribution of this work and lack of its acknowledgment within the professional literature.