Acute kidney injury (AKI) is defined as an increase in serum creatinine or a decrease in urine output over hours to days. A thorough history and physical examination can help categorize the underlying cause as prerenal, intrinsic renal, or postrenal. Initial evaluation and management of AKI in the community setting includes laboratory work-up, medication adjustment, identification and reversal of underlying cause, and referral to appropriate specialty care. Even one episode of AKI increases the risk of cardiovascular disease, chronic kidney disease, and death. Therefore, early determination of etiology, management, and long-term follow-up of AKI are essential.