Large stand-replacing fires at intervals of 50 to 500 years were responsible for the vegetation patterns of parks and wilderness areas in the Boreal, Great Lakes-Acadian, Rocky Mountain, and Douglas-fir regions. Fire recurrence is closely linked to stand age in some ecosystems. Prescribed crown fires and underburnings could help begin fire management safely. In the far North, natural crown fire regimes still exist, and in some Rocky Mountain units such fires are being successfully managed. Improvements in techniques and fire control technology should make fire management feasible in more areas. Restoration of natural regimes is vital to preserving landscape diversity.