Two experiments examined the impact of attention on sensorimotor skills. In Experiment 1, experienced golfers putted under dual-task conditions designed to distract attention from putting and under skill-focused conditions that prompted attention to step-by-step putting performance. Dual-task condition putting was more accurate. In Experiment 2, right-footed novice and experienced soccer players dribbled through a slalom course under dual-task or skill-focused conditions. When using their dominant right foot, experts again performed better in the dual-task condition. However, when using their less proficient left foot, experts performed better in the skill-focused condition. Novices performed better under skill-focus regardless of foot. Whereas novices and the less-proficient performances of experts benefit from online attentional monitoring of step-by-step performance, high-level skill execution is harmed.