Bioclimatic architecture is a world-known trend in building architecture design, but in Latvia this term is scarcely used. While studying the theory of architecture and analysing practical examples, the author of this Paper has endeavoured to outline the role of bioclimatic factors in the formation of features of regional architecture. This Paper renders a historical outset of incoming of sustainable development ideas into architecture. With a glance to the urgency of energy–efficient building in Latvia the Paper also affords a look at the differences between bioclimatic architecture and energy-efficient building