The economic assessment of treatments or medical strategies has been the subject of an increasing number of publications. The elevated costs and relative lack of efficacy of many treatments of chronic diseases such as lung cancer are an added impetus to such analyses. In the first part of this review, we summarise the theoretical basis of economic assessment, the tools available and the limitations of these methods. In the second part, we examine their application to the treatment of lung cancer. We discuss the evaluation of the cost of these cancers to society, economic assessment of new chemotherapeutic drugs, and the place of cost-effectiveness analysis in randomized trials. In the last part, we outline the interest and future of such considerations for clinicians. These methods, which provide complementary data for clinicians when making decisions on therapeutic options, will be adopted more widely in coming years.