Epidemiology, by imposing methodologic control and a numerate approach, can provide major contributions to"capture" and understand psoriasis. Certainly, more efficient research strategies in many areas are needed, and consensus should be reached on critical issues such as case classification and onset definition. Multidisciplinary research work and large study networks are requested to progress in a systematic way. One of the ultimate goals of epidemiologic investigations is to identify causes, with a view to developing preventive strategies. It is plausible that the possibility of modulating clinical expressiveness of the disease instead of treating active lesions may become available to clinicians (disability prevention) based on future etiologic research.