Water resources in the U.S. are managed under a complex interplay of federal, state, and sometimes local policies. In the Western U.S. (west of the Mississippi River, for this talk), the historic goal of federal water policy was to encourage settlement and economic development. Many of the early water rights were allocated to agriculture. Since water rights are prioritized as “first in time, first in right”, urban and industrial uses often have lower seniority rights than agriculture. There is controversy about the temporal priority of Tribal water rights that may have been recognized under treaties but not in state or federal policy. Environmental requirements were not generally recognized by state and federal policy, but some would argue that the environmental requirements predate any other allocation. In most states' water policy, groundwater and surface water resources are treated as independent, though they are highly interactive. Overdraft of groundwater has caused reductions in spring flow and base flow of rivers and streams. Water rights allocations and trans-boundary basin delivery obligations were often based on an inadequate or erroneous understanding of the quantity of water supply and exceed what is produced in a basin, particularly during times of extended drought. Change in societal goals and priorities is forcing innovations, a few of which will be presented, to efficiently and equitably transfer or allocate water rights to new uses.