Nitrous oxide (NO) is underutilized in ambulatory urology. Here, we review available data regarding application, efficacy, and side effect profile of NO in ambulatory urologic procedures. Data were available from 11 studies. NO has been described in the setting of transrectal ultrasound-guided prostate biopsies, flexible cystoscopy, ureteral stent placement, and extracorporeal shockwave lithotripsy in adult patients and catheterization in children. Studies showed significant improvements in peri-procedural pain and anxiety relative to alternative (or none) forms of analgesia. Adverse effects were rare and self-limited. More widespread use of NO may result in cost savings and better patient tolerance with outpatient procedures.