To provide an overview of the efficacy and safety of lemborexant in the treatment of insomnia disorder by assessing the currently available literature. A literature search of PubMed was performed (2010 to March 2021) using the following search terms: lemborexant, sleep, orexin. All relevant English-language studies were reviewed and considered, with a focus on phase 3 trials. The efficacy and safety of lemborexant in the treatment of insomnia disorder in adults was demonstrated in 2 phase 3 trials. Lemborexant significantly reduced latency to persistent sleep compared with placebo. The first study also demonstrated a significant reduction compared with the active control zolpidem ER. Somnolence and headache were relatively common, but the marked adverse effects associated with other medications commonly used to treat insomnia, such as cognitive and psychomotor impairment and complex sleep-related behaviors, were not observed. Although nonpharmacological therapy is considered first-line treatment for insomnia disorder, pharmacological treatment is most commonly utilized. Lemborexant is a viable pharmacological treatment option for patients who are unable to tolerate the adverse effects associated with the most commonly prescribed medications for insomnia, such as benzodiazepines and sedative-hypnotics (Z drugs). This is especially true for geriatric patients, who may be more sensitive to these adverse effects. Lemborexant can be recommended to treat insomnia disorder when pharmacological treatment is warranted. It has demonstrated efficacy in clinical trials and is likely better tolerated than most currently available treatment options.