The aims of the population-based, cross-sectional survey "Study of Health in Pomerania" (SHIP) are to describe prevalences and distributions of a broad range of diseases, as well as environmental and behavioural risk factors in the region of Pomerania (North-eastern Germany). The examinations are performed in two study units by different physicians, technicians and interviewers and laboratory analyses in two separate laboratories. In addition, the study will take at least 3 years and approximately 7000 persons will be examined. Because of the design of the study a special concept of quality assurance is indispensable. In the present paper methods are presented for quality assurance and control in anthropometry, ECG, echocardiography, abdominal sonography, carotid ultrasound, sonography of the thyroid gland, blood pressure measurements as well as clinical laboratory analyses. The technical control protocols, the training programmes of the observers and methods to establish observer and method variabilities are presented by means of typical examples. The logistic, personal and technical measures for quality assurance and control require appropriate attention. The methods and procedures presented here are expected to provide an effective instrument to continually monitor the quality of medical examinations in the SHIP study.