This document discusses using portfolio theory and utility theory to optimize the market mix of tourist origins for destinations. It presents research applying this approach to optimize France's portfolio of European tourist origins from 2007-2013. The portfolio model calculates the optimal proportions of each origin to maximize return for a given risk level based on growth rates, variances, and covariances. The results show France's current portfolio is sub-optimal with higher risk than optimized portfolios providing similar returns. Accounting for a decision maker's risk aversion allows identifying a preferred efficient portfolio to improve destination performance.