Decisions to relocate endangered freshwater mussels as a way to manage populations can be controversial and are inherently difficult because of uncertain outcomes, often multiple and sometimes conflicting objectives, and differing opinions on facts and values. Current decisions on when, where, and how to relocate mussels are at best ad hoc. Structured decision analysis is a scientific approach that can help resource managers evaluate decisions and deal with uncertainty inherent in predicting species response to a management action.  Structured decision making provides the framework for careful thinking about objectives, criteria and alternatives, prediction of benefits and biological risks of each alternative, and effective monitoring of species response. The tools and techniques used in this approach, including influence diagrams, decision trees and Bayesian networks, clarify the important parameters that could influence the desired outcome. Adaptive management, a special case of structured decision making, allows for iterative learning through a process of evaluating alternatives through management experimentation. We use the relocation of the endangered northern riffleshell, Epioblasma torulosa rangiana, from the Allegheny River to other watersheds as a straw man to illustrate how structured decision making could be applied.