Psoriasis and its related manifestations, including psoriatic arthritis, are prevalent disorders in the Western world, particularly among Caucasians. The study of these disorders in Latin America lags way behind the study of other more common rheumatic disorders, such as rheumatoid arthritis and systemic lupus erythematosus. From the scarce evidence available, however, it appears that the prevalence and incidence of psoriasis and psoriatic arthritis are lower than in other parts of the Western world and almost negligible among natives from the Andean region, although confirmatory epidemiologic studies are lacking.