Zolpidem (Ambien), a nonbenzodiazepine hypnotic, is indicated for the short-term treatment of insomnia. Because it has become the most widely prescribed sleep aid in the United States, it is being increasingly detected in a variety of forensic specimens, and its interaction with other medications is being questioned. We present a comprehensive overview of the basic chemistry, pharmacokinetics, and pharmacodynamics of zolpidem; its interaction with other prescription drugs; its effects on driving and motor skills; and its analysis and interpretation in forensic casework.