Sleep problems are very prevalent during infancy. The most common problems are those related to night wakings and sleep-disordered breathing (SDB). Most common night waking problems do not have identified physiologic etiology. Their causes appear to be behavioral or developmental by nature, and they usually respond well to behavioral interventions. SDB may result from a variety of anatomic and neurologic factors and is associated with a variety of medical and developmental disorders. Because of the high prevalence of sleep problems during infancy, their persistence, their potential adverse developmental effects, and the positive treatment outcomes, pediatricians should serve as the primary address for screening and referral to proper assessment and treatment.