During the past five years, through the discovery of significant accumulations of oil and gas, the Triassic formations of the Peace River area have assumed a position of economic importance. The Triassic has been subdivided into six formations, Toad-Grayling, Liard, Halfway, Charlie Lake, Baldonnel, and Pardonet, using wherever possible the names assigned by others working in the area. Each formation has been described, and type sections designated for the Halfway, Charlie Lake, and Baldonnel formations. Isopachous maps and, for most of the formations, lithofacies maps have been drawn to show the lateral variations within these formations. Correlation has been established with the outcrop sections of the adjacent Rocky Mountains foothills, together with limited age determinations. The depositional history is reviewed, including a discussion of the evaporitic cycle of the Upper Triassic.