Urban stormwater significantly impacts not only water quality but also the physical stability and condition of headwater streams due to flashy and frequent erosive flows.   The U.S. Environmental Protection Agency (EPA) recently announced the release of A Function-Based Framework for Stream Assessment & Restoration Projects. According to EPA, stream restoration is relatively young and still evolving, yet it is recognized as a billion-dollar industry. This document discusses how stream functions — hydrology, hydraulics, geomorphology, physicochemical properties, and biology — are interrelated and build on each other in a hierarchy. The framework focuses on each of these functions, discussing the development of function-based assessments, restoration goals or performance standards. The document also places the restoration efforts that occur within a stream reach into a watershed context, emphasizing site selection.