The present paper analyses the Québec-Maine boundary as an example of political geography in a regional and systematic framework. The principal questions involve the various technical aspects which constitute the formation of the boundary and the ambiguous character of this border-problem. The article illustrates the manner by which the problem has been solved by a series of compromises. In spite of its recent nature, the Québec-Maine border shows the same anomalies that are found in certain much older cases. It is demonstrated here that for the Québec-Maine boundary the concepts of artificial and natural boundary have no meaning. Finally, since the American part of the boundary is a pene-enclave, it has favoured the establishment of an industrial monoactivity on the Québec side. Even today, owing to the massive depopulation which heavily mortgages the future of the region, the existence of the boundary is once again being questioned.