The paper reflects the priority role of preliminary and periodic medical examinations in the system of measures implemented by therapeutic-and-prophylactic institutions of the Ministry of Railway of Russia. It gives a comprehensive assessment of the medical, social, and economic aspects of the efficiency of preventive medical examinations. Emphasis is laid on the necessity of elaborating methods to evaluate the economic efficiency of medical measures under the conditions of market economy. At the same time, light is shed on the difficulties available when a full-scale, within the whole industry, economic evaluation of periodic medical examinations is made. The role of a cost-effect analysis is shown as the most flexible existing principle in the evaluation of the efficiency of medical preventive measures.