The aim of this article is to review recent advances and the latest research trends in psychiatric epidemiology. Examination of mental disorders prevalence delivers important information about the mental state of society and need for professional psychiatric care. The 12 months prevalence estimates are 30% for any mental disorders. Knowledge about historical methods of data collecting helps to understand psychiatric epidemiology better. We overview few generations of research that differ in methodology. The most common difficulties observed during that kind of research will be described. Available methods of examination of mental disorders prevalence will be presented in this article. The most significant results of international WHO epidemiologic project will be discussed. We also point out future challenges for psychiatric epidemiology and predict the systemic solutions that make intercultural comparisons possible.