Prescribed natural fires have been managed in wilderness areas of the U.S. Forest Service since the mid-1970's. Most of the prescribed natural fires have occurred in larger wilderness areas where the probability of escape is low. Forty-three of the 59 wilderness areas managed by the U.S. Forest Service in Oregon and Washington are less than 100,000 acres (45,000 hectares) in size, and represent 30% of the acres. Planning and implementing prescribed natural fires in smaller wilderness areas is complex. However, computer-based analytical tools for weather data analysis, fire spread predictions, and risk assessment enhance our ability to include small areas in the program. The Mill Creek Prescribed Natural Fire, Ochoco National Forest, in September 1995 is one example of how these new capabilities were applied to successfully manage a prescribed natural fire in a small wilderness. © 1998, Tall Timbers Research, Inc. Abstract reproduced by permission.