In many countries around the world, biobanks have become crucial resources for the conduct of biomedical research, facilitating many kinds of research, including international collaborations. The focus of this special issue is on a looming ethical issue that has become a focus of debate-the return of research results and incidental findings to biobank participants. Although the articles in this issue do not provide a final answer to the ethical, legal, and social dilemmas that arise in the context of the return of results, the intent of the collection is to approach this issue from multiple perspectives and within an international context spanning the United Kingdom, continental Europe including Eastern Europe, the United States, and the Middle East.