Based on optimal foraging theory, we propose a metric that allows evaluating the goodness of goal systems, i.e., systems comprising multiple goals with facilitative and conflicting interrelations. This optimal foraging theory takes into account expectancy and value, as well as opportunity costs, of foraging. Applying this approach to goal systems provides a single index of goodness of a goal system for goal striving. Three quasi-experimental studies (N = 277, N = 145, and N = 210) provide evidence for the usefulness of this approach for goal systems comprising between three to 10 goals. Results indicate that persons with a more optimized goal-system are more conscientious and open to new experience, are more likely to represent their goals in terms of means (i.e., adopt a process focus), and are more satisfied and engaged with their goals. Persons with a suboptimal goal system tend to switch their goals more often and thereby optimize their goal system. We discuss limitations as well as possible future directions of this approach.