Editors' Summary: Looking at extremes may seem futile when dealing with important environmental issues: the outcome on either end of the spectrum is almost always objectionable. Yet they are the bounds within which the solution lies. Thus, finding the balance between the endpoints is imperative. The Colorado River and its related international water law is the story of how the context of the times drives the evolution of law within such extremes. This Article looks at the evolution of international fluvial law surrounding the Colorado River regarding quantity, quality, conservation, and ecological needs, which will continue to adapt slowly as society changes where the balance is struck.