Insomnia, which is defined as either difficulty falling asleep or staying asleep, is a prevalent sleep disorder among primary care patients. Unfortunately many patients do not report their sleep disturbances to their providers and fewer patients seek treatment. Insomnia is associated with a large economic burden and can lead to medical complications, psychological disorders and poor quality of life. Understanding the pathophysiology of insomnia will lead to a better understanding of the mechanism of action of the drug treatments, including two of the newest medications to be approved. It is important to appropriately diagnose and treat insomnia to prevent complications. Treatment also includes counseling on proper sleep habits and limiting risk factors that can cause this sleep disturbance.