Summary: Long leadtimes in completing nuclear powerplants have contributed to high capital costs and sometimes to cancellation of units. Currently, 10 or more years of leadtime consists of about 2 years of planning, 2 or more years of construction permit review by the Nuclear Regulatory Commission (NRC), and 6 or more years of construction. The NRC operating license review parallels part of construction. To reduce leadtimes, the NRC has begun to: (1) authorize limited construction following completion of the environmental and site suitability portions of reviews; (2) encourage development and use of standard nuclear powerplant designs; and (3) accept applications for site approvals up to 5 years before utilities apply to begin construction. Times have not been reduced as expected because of: delays in State approval; time consumed for environmental statements and public hearings; the fact that benefits from standard designs will take time; and because some issues, such as environmental factors, cannot be decided at an early stage. GAO concluded that many factors will continue to prevent reduction of leadtimes, including growing State and local requirements, public concern, court decisions, and technological changes. It was recommended that the NRC should work jointly with states to identify and compare legal and procedural requirements.