The effectiveness of competition plans on athletes' performance outcomes was assessed while accounting for the mediating influence of state depression and self-efficacy. Competition plans reflect an integrated and personalized plan that consists of a set of decision-making rules based on the principles of self-control and self-efficacy development that are tailored to the specific demands of an upcoming competition in a given sport and highly individualized to take into account the specific qualities of the athlete. The relationship between the development of a competition plan and athletes' evaluations of their competitive outcomes was of interest. 11 elite athletes participating in 104 competitions involving 7 different sports participated. Results support the beneficial effect of a well-developed competition plan in affecting athletes' perceived performance; the relationship was mediated by state depression and self-efficacy. Coaches and sport psychologists should devote increased attention to the development and refinement of athletes' precompetition performance plans while also considering participants' self-efficacy and mood characteristics.