The problem of distribution of forces among synergistic muscles at a joint is examined. In order to arrive at a unique solution for the redundant system it is assumed that the solution represents an optimal response in terms of total muscle effort. The minimum muscle effort can be related to the concent of reciprocal inhibition. The nature of the resulting mathematical formulation is illustrated by a simple two tendon model. The formulation for a general multiaxial joint is then given, along with a general principle concerning the nature of resulting solutions. Results for two examples based upon a simplified biaxial model of the wrist are presented. Finally, the nature of several implicit assumptions in the analysis are reviewed and their consequences discussed.