This chapter highlights the key discoveries in neurophysiology that elucidate how brain function shapes motor learning. It provides an overview of the stages of motor memory formation and introduces the concepts of early and late learning. The chapter discusses the neurophysiological mechanisms underpinning the progression through these stages. It explores some modulators of motor skill learning, highlighting the effects of sleep and acute cardiorespiratory exercise on memory. The chapter presents current research related to motor learning and its underlying neurophysiology, with a focus on skills and mechanisms most relevant to sport. Changes in brain physiology and anatomy underpin the learning of new motor skills, as well as modification of existing ones. Neuroplasticity is the capacity of central nervous system to undergo functional and structural adaptation in response to experience, including practice. Repeatedly performing motor skills in practice stimulates experience-dependent plasticity throughout the brain. These changes are the result of alterations in the brain at cellular and systems levels of organization.