As water becomes increasingly scarce, it becomes imperative to make it easier to realloc ate water among various bene fi cial uses, including those currently identified and those likely to arise in the future. To do this we must find ways to con tinu ally integrate new sci ent ific know ledge (and advances in modeling) into the institutional structures for water management. Adaptive management, where in teg rated modeling serves as a backbone for monitoring and decision-making, would enable us to do this. We begin this chapter by reviewing arguments made by the authors of various chapters in this book. We have discussed modeling as the basis for decision-making (Chapter 2), and investigated the climate and water supply con text of New Mexico (Chapters 3-4). We have ex plored cultural, legal and institutional issues (Chapters 5-8), and we have discussed new institutions and players, and associated issues (Chapters 9-13). We will then turn to a discussion of constraints and challenges that any proposed change to water management in New Mexico will face. We offer these before proposing changes so as make very clear the overall magnitude of the task. In doing so, we take a broad look at lessons that have been learned re gard ing how to manage the envir on mental commons, which sets the stage for a discussion of the signi fic ant mat ters that need to be addressed. We then list and discuss the im port ant lessons that have been learned from the his tor ical record of our evolving management of the envir on mental commons. These set the stage for a discussion of im port ant elements that must be con sidered in any dialogue re gard ing future water management in New Mexico. Finally, we offer some thoughts on how New Mexico can achieve better water management.