A spectacular forest in the center of the Crown of the Continent Ecosystem (CCE) cuts a 15- by 5-km swath along the Flathead River's South Fork around Big Prairie in the middle of the Bob Marshall Wilderness Area in Montana (Figure 13- 1). This wide valley bottom, which contains two patches (of about 1,000 ha each) of the last vestiges of the historic ponderosa pine ecosystem in the CCE, provides a local context and a case example for our discussion of fire dynamics in this chapter. The Big Prairie ponderosa pine (see Chapter 2 for scientific names not given in this chapter) ecosystem is a consequence of a special fire regime that has been altered during the last century. As a result, this ponderosa pine forest is declining rapidly, and the causes of its decline are similar to those in many other fire-dependent ecosystems in this diverse region. Here we discuss the many and varied fire regimes of CCE landscapes, using the Big Prairie ecosystem to demonstrate the challenges of managing fire.