Districts across the country, including some of the nation's largest, are facing a spate of superintendent vacancies. Schools chiefs or interim superintendents will be leaving this year or next in at least 17 well-known districts, including Baltimore, Maryland; Boston, Massachusetts; Clark County, Nevada; Indianapolis, Indiana; and Wake County, North Carolina. While school officials in some places, such as Baltimore, Boston, and Oakland, California, have indicated they intend to continue on paths laid out by their departing leaders, the turnover elsewhere may signal major changes--and go hand in hand, in some cases, with a shift in district priorities or governance restructuring.