The traditional study of infant locomotion focuses on what movements look like at various points in development, and how infants acquire sufficient strength and balance to move. We describe a new view of locomotor development that focuses on infants' ability to adapt their locomotor decisions to variations in the environment and changes in their bodily propensities. In the first section of the chapter, we argue that perception of affordances lies at the heart of adaptive locomotion. Perceiving affordances for balance and locomotion allows infants to select and modify their ongoing movements appropriately. In the second section, we describe alternative solutions that infants devise for coping with challenging locomotor situations, and various ways that new strategies enter their repertoire of behaviors. In the third section, we document the reciprocal developmental relationship between adaptive locomotion and cognition. Limits and advances in means-ends problem solving and cognitive capacity affect infants' ability to navigate a cluttered environment, while locomotor development offers infants new opportunities for learning.