The book "Reclaimed Avant-garde: Spaces and Stages of Avant-garde Theatre in Central-Eastern Europe" is the outcome of a conference held in November 2017 at the Zbigniew Raszewski Theatre Institute. The book is also a next stage of the process of recognizing and restoring the importance of avant-garde theatre search, which in the 1920s and 1930s exploded with a real wealth of ideas that has evoked admiration, appreciation and amazement lasting until today. The book consists of 14 reports prepared by researchers from 11 countries of the region, from Latvia to Slovenia, and from Georgia to the Czech Republic. These texts present avant-garde discovery and transformation of theatre space, work with its dramaturgy, innovative set design ideas. At the same time they remind us about both male and female artists who drew from their unusual imagination, and are nowadays recognized (yet not always) only by the local specialists and researchers. The book allows us to discover the real richness of inspiration, refreshing at the same time the way of thinking about space and theatre.