Summary : The Stone Age in the Congo Basin has a rich yet troubled research tradition. During the colonial era, prehistory was high on the research agenda in search of ancient sites yet slipped into the background within the context of postcolonial states focusing on recent history and the last five thousand years. In archaeological terms, attention shifted from flaked stone to pottery and iron as material traces of the past. Issues with site integrity and lack of absolute chronology imply that often the identification of the various phases of the Stone Age, as well as of cultures and industries, is essentially based on typo-technological characteristics. A clear challenge both for studying and for occupation during the Stone Age in the Congo Basin is the rainforest. Though poorly documented at the time of Stone Age occupations, the last twenty-five hundred to four thousand years yield a very dynamic picture of this once-thought immutable biome. Despite all methodological and factual caveats and the disparity of the archaeological record in terms of chronological, typo-technological, behavioral, and environmental characteristics, there can be no doubt about the flexibility and adaptability of human populations and their ancestors in the Congo Basin. The field of genetic studies is increasingly contributing to understanding this fascinating human history of rainforest occupation.