This article summarizes what has been learned from the isotopic investigations of the settlement of the North Atlantic. In addition, I consider what questions remain and where future research may take us. I begin with a brief synthesis of the interpretation of human mobility in the North Atlantic region with a specific focus on the issue of local vs. non-local individuals on Iceland and Greenland. The results of the isotopic analyses provide new insight on the settlement of the North Atlantic. It is also possible to compare the results from Iceland and Greenland to examine similarities and differences in the process of colonization. The article concludes with a review of the research questions raised in the introduction to this volume, some of the answers that have been found, and some of the questions that remain.