Compressed air foam, which is a relatively new development in the realm of fire suppression technology, has gained wide acceptance in the wildland and rural fire protection environments. Several of the characteristics and capabilities that have been reported by users of compressed air foam suggest that it could be a valuable addition to the arsenal of urban as well as rural fire departments. The potential benefits of a transfer of compressed air foam technology to the urban environment were recognized by the United States Fire Administration, which provided the opportunity to conduct the field evaluation program that is described in this report.