Animal contests govern access to key resources and are a fundamental determinant of fitness within populations. Little is known about the mechanisms generating individual variation in strategic contest behavior or what this variation means for population level processes. Cognition governs the expression of behaviors during contests, most notably by linking experience gained with decision making, but its role in driving the evolutionary ecological dynamics of contests is only beginning to emerge. We review the kinds of cognitive mechanisms that underlie contest behavior, emphasize the importance of feedback loops and socio-ecological context, and suggest that contest behavior provides an ideal focus for integrative studies of phenotypic variation. Animal contests are important determinants of fitness. Cognition mediates contest behaviors, but its role is underappreciated. New theory, technologies, and methodologies facilitate the study of contest cognition. We develop a framework linking cognition, contests, fitness, and ecology.