Development of a high level of motor skill performance requires practice. Interestingly, human functional MRI studies show that motor skill training can lead to decreased functional activation in the primary motor cortex (M1), suggesting that practice increases motor system efficiency. To examine this, Picard et al. measured functional activity and neuronal firing in M1 of monkeys while they performed sequential reaching tasks that were designed to engage newly learnt or highly practised motor skills. Neuronal firing rates were similar in both types of tasks, but functional activation was decreased in the tasks engaging well-practised movements, indicating that practice increases the efficiency of M1 neuronal activity.