Igloo is one of the few Eskimo words that most white people understand, and shares with kayak and oomiak the distinction of appearing in almost all English dictionaries and occasional cross-word puzzles. The great majority of Eskimos, however, have never seen a snow house and it is only among the Central tribes (roughly those living in Canada east of the Mackenzie) that it has reached its fullest development. One result of this is that it has seldom been adopted by white travellers except in this region, though here it has been shown time and again during the last hundred years to be the most suitable form of dwelling for winter travel. It does not necessarily follow that the snow house would be as satisfactory in other polar regions, but I think that there are occasions when it could be used by expeditions to their advantage. Certainly all serious travellers should know how to build one in emergency. This is by no means so difficult as it is reputed to be, and two or three days' practice should give a reasonable proficiency. First I shall describe the normal building method of the Igloolik tribe, and then give various modifications which may be preferred according to individual taste.