Up until 1968, fires were suppressed in national park units to the extent possible. The growing recognition of the importance of fire as a part of a naturally functioning ecosystem led, however, to a more complex fire management policy. Fires caused by people are always extinguished as quickly as possible, but decisions about managing naturally-ignited fires take into consideration many factors; these factors include the proximity of the fire to developed areas and private property, forecasts of weather, and the availability of firefighters and equipment in case containment becomes necessary.