Three of the most common sleep disorders are narcolepsy, obstructive sleep apnea, and restless legs syndrome. Narcolepsy is a chronic sleep disorder characterized by overwhelming daytime drowsiness and sudden attacks of sleep. Sometimes, narcolepsy can be accompanied by a sudden loss of muscle tone (cataplexy). Obstructive sleep apnea is characterized by airway collapse that causes greatly decreased or absent breathing. Restless legs syndrome is characterized by an irresistible urge to move the legs. These conditions lead to insomnia, the chronic inability to fall asleep and to stay asleep. Patients who suffer from insomnia may experience sleepiness during the day, feel fatigued, and experience difficulty with concentration or memory. Sleep disorders can cause significant medical and psychological health conditions. The basic treatment for all three is good sleep hygiene. Medications may provide relief from the signs and symptoms. The use of a CPAP machine and other oral devices may also alleviate insomnia due to sleep apnea. A case study is discussed that illustrates the benefit of good sleep hygiene and CPAP for a male diagnosed with sleep apnea.