Delirium is described as a manifestation of acute brain injury and recognized as one of the most common complications in intensive care unit (ICU) patients. Although the causes of delirium vary widely among patients, delirium increases the risk of longer ICU and hospital length of stay, death, cost of care, and post-ICU cognitive impairment. Prevention and early detection are therefore crucial. However, the clinical approach toward delirium is not sufficiently aggressive, despite the condition's high incidence and prevalence in the ICU setting. While the underlying pathophysiology of delirium is not fully understood, many risk factors have been suggested. As a way to improve delirium-related clinical outcome, high-risk patients can be identified. A valid and reliable bedside screening tool is also needed to detect the symptoms of delirium early. Delirium is commonly treated with medications, and haloperidol and atypical antipsychotics are commonly used as standard treatment options for ICU patients although their efficacy and safety have not been established. The approaches for the treatment of delirium should focus on identifying the underlying causes and reducing modifiable risk factors to promote early mobilization.