The beneficial contact between the practitioner and the clinical laboratory is jeopardized by poor use and overuse of laboratory services. Physicians who order tests excessively put an unjustified burden on the laboratory. This overuse does not contribute to the quality of medical care, does not shorten hospital stay, nor reduce mortality. In clinical departments of another large university hospital there were differences of up to 82% in the number of tests performed, despite similar size and function of the departments. Among the reasons for overuse of laboratory tests is lack of an incentive for patient, physician or clinical department to reduce costs. The fragmentation of laboratory services, the conflicting interests of hospitals, as well as the multitude of personal, institutional and professional interests, also contribute to the variety and excess of superfluous laboratory tests. Analysis leads to suggestions for simple methods to contain the number and cost of laboratory services. Introduction of a reimbursement structure and introduction of new test request forms without a "menu" of tests, and education of practitioners in appropriate test-ordering would promote more appropriate utilization of laboratory services. The educational initiatives would provide guidelines for the clinician as to optimal test selection, the availability of cost-efficient tests, and optimal utilization of the laboratory. Based on decision-analysis methodologies, available test profiles should be restructured to match clinical problems, treatment, and patterns of clinical thinking. Improved access to information and computer-based analysis of data should improve test selection. The suggested methods of reducing unnecessary test ordering, and strategies for more discerning use of laboratory services will undoubtedly improve the practice of medicine and improve the laboratory-physician relationship.