Under their traditional jurisdiction over land use, the states permit and site interstate electric power facilities that traverse their boundaries. This jurisdiction may pose an obstacle to the development of new interstate transmission facilities. For that reason, Congress enacted section 216 of the Federal Power Act, which, in limited circumstances, will preempt state law and authorize the Federal Energy Regulatory Commission to permit interstate transmission lines. The implementation of section 216, however, has been frustrated by judicial challenges in federal courts. Seven years after the enactment of section 216, FERC has yet to exercise jurisdiction over the construction of an interstate transmission line. Under little threat of federal preemption, state jurisdiction over transmission facilities could pose an obstacle to the development in the Mid-Atlantic region of “backbone” transmission lines needed to provide electric power to the Washington-Baltimore-Northern Virginia area. Thus far, however, state proceedings to permit and site one such line rebut the notion that state jurisdiction will stymie the development of interstate transmission facilities.