The book "Transition Economics: Two Decades On" celebrates the shift from socialism to capitalism over the past twenty years. It serves as a textbook for undergraduate courses, focusing on the economic changes in ex-socialist European and Asian countries like Russia and China. The authors discuss the initial conditions, transition policies, and performance of these countries during the shift. They believe that studying these transitions can provide insights into economic theories, policies, and lessons that can be applied beyond just this specific historical period and region.