HALTgeben is a cluster-randomized controlled trial among health care workers and clients from 10 hospitals and one residential home in Germany. Aim of the study is the reduction of physical and psychosocial workload among the health care workers and thereby a) increase their physical and mental work ability b) increase clients‘ satisfaction with health care. Medical Sociology at Ulm University is responsible for the study design and process as well as outcome evaluation of intervention effects. Interventions will be initialised by the health care workers  in a participative process. Arbeit und Zukunft e.V. will host the interventions. The study design comprises the measurement of sociodemographic information and of work-related stress, work ability and health of health care workers as well as client satification with the help of standardized well-tested questionnaires. The measurement will help to evaluate the intervention success and will be conducted at three points of time :  immediately before intervention onset, immediately after the realization of first interventions and at least twelve months after the beginning of interventions to evaluate long-term effects. Regarding process evaluation a new standardized questionnaire will be developed to test motivational aspects of and self-efficacy related to the intervention process among health care workers.