Hydro responded to demands from residents of farms and hamlets for a fair share of the public power that was being distributed to municipalities in southwestern Ontario in 1910. It extended its transmission lines along the back concessions of the region, developed new agrarian applications for electricity, and devised a rural rate schedule capable of attracting new customers and encouraging electrical consumption. Provincial government funds were allocated to Hydro for rural development in the 1920s and moderate growth was maintained until World War II interrupted the rural construction program. After the war, however, rural electrification in southern Ontario progressed rapidly until 1958 when provincial money for that region was substantially reduced and Hydro redirected its attention to the needs of the North. While Fleming shows that the public utility proved responsive to changing economic conditions, technological developments, and political considerations as it became a world leader in rural electrification, he also presents evidence of the policies and methods which have engendered negative sentiment toward Ontario Hydro. For example, he reveals that the power at cost policy was both a way to achieve price reduction and a strategy for price maintenance. In describing the various influences on Ontario Hydro's program of rural electrification, Fleming has drawn from an impressive array of archival and newspaper sources, including the Ontario Hydro Archives, the Ontario Archives of the Hydro-Electric Commission, and files in the office of the Ontario Premier. Power at Cost will become the standard reference on the subject of rural electrification in Ontario.