In order to better delineate affiliations between breeding, molting, and staging areas of the small Harlequin Duck (Histrionicus histrionicus) population wintering in eastern North America, in April 2001 satellite transmitters were implanted in eight adult males at Isle au Haut, Maine, a major wintering area for this population. Two birds were confirmed breeding on rivers on the Gaspé Peninsula, Québec, two birds molted in northern Labrador, and four birds migrated to southwestern Greenland during the molting season, including one bird that bred in Québec. The four birds tracked to southwestern Greenland likely molted there, although molting could be confirmed for only one bird. All birds tracked to Greenland, to breeding areas, and to molting locations returned to wintering sites in Maine the following wintering season. This study is the first confirmation of wintering male Harlequin Ducks from eastern North America molting in Greenland.