The IIGA liaises with the member island associations and with sponsors of the games.

Constituents come from islands in, or associated with, eight sovereign states (Denmark, Estonia, Finland, Malta, Norway, Spain, Sweden, and the United Kingdom).

Ynys Môn (Anglesey), Frøya and Hitra have bridge or tunnel connections to their mainlands.

Greenland is by far the largest island, and is magnitudes bigger than all the rest combined, but is very sparsely populated.

There must be a local association of governing bodies of at least two sports in the IIGA program at which the island can "adequately" compete.