The organization of the UISPP XVI world congress in Florian?polis was the occasion to focus a certain number of themes that are preferably dealt with at a transcontinental scale. Several sessions discussed the issue of transition mechanism (technological, social, economic, and their climatic and environmental contexts). Marcel Otte opens the volume, focusing on the specific role of straits, a topic that is also at the foundation of Judith Carlin's et al. paper. Contributions by Fabio Parenti et al., Gustavo Wagner and Mercedes Okumura et al., discuss the human adaptations in different contexts in Brazil, during the early and middle Holocene. First farming societies in Southern America and in Europe are approached in the papers by Marcel Otte and Jorge Oliveira et al., while the transition into more complex societies, bearing metallurgical knowledge, is the focus of papers by Leonor Rocha et al., C?t?lin Laz?r. Finally, classic contexts on both sides of the Atlantic are revisited by Erika G?mez andby Carolina Dias.