The medicalization of life has been encouraged by an excessive interest in health as an end in itself rather than as a means for a better life. This new concept of health has stimulated the growth of the secondary market of health and, in analogy with the knowledge society, the emergence of what is known as the "health society". Among the most popular health "products" are diagnostic tests, explaining the enthusiasm for screening programs and the new genetic technologies, especially in the detection and prognosis of cancer. Because of the iatrogenic potential of diagnostic tests and the unnecessary demand caused by their excessive use, this phenomenon is a matter of public health concern. Health administrations must face this challenge with a diverse range of interventions that range from clinical management to policy formulation including the improvement of diagnostic research. The contribution of diagnostic research has so far been limited by its irregular quality.