Engineers' goals and priorities may shift for a variety of reasons. Changes in fashions, markets or politics may make approaches that were once considered desirable or necessary seem unattractive or inappropriate. Or engineers and society at large may learn new things that lead to a reevaluation of results and a reorientation of efforts. Few better examples of this can be found than the re-engineering of South Florida's rivers and wetlands. The Kissimmee River begins near Orlando and flows southward for about 100 miles into Lake Okeechobee. Historically, it meandered through a one- to two-mile wide flood plain, covering all but a small portion of the land for most of the growing season. In periods of large storms or hurricanes, waters from the Kissimmee and other rivers would destroy homes and crops over a wide area. lb reduce flooding, the US Army Corps of Engineers straightened the river in the 1960s and drained much of the nearby wetlands. Even before the project was completed in 1971, however, it was clear that this effort had resulted in devastation of wildlife habitats and the displacement of many animal and plant species. State and federal agencies decided that engineers' efforts needed to be reoriented toward undoing the damage. Recovery of the Kissimmee River became one of the most ambitious restoration projects ever undertaken. Slowly the Corps of Engineers and the South Florida Water Management District are returning major portions of the Kissimmee from a canal back into a meandering river, to make the environment of South Florida once again hospitable to its historic inhabitants. Re-examining the definition of the problem holds great potential for generating new possibilities in the business realm. One of our favorite stories is that of P&G's creation of the Swiffer mop. After decades of focusing on the problem of producing more effective detergents, P&G re-oriented its thinking to focus on creating a cleaner floor, as well. This led to the realization that the detergent was only part of the solution, and that significant opportunities existed in producing a better mop.