Acute diverticulitis is an emergency surgical condition that is commonly managed an acute surgical unit model. Operative surgery is indicated in selected situations including generalized peritonitis or fistulous disease; however, limited data exist on how borderline patients potentially needing surgery may be salvaged by close clinical management with modern interventional techniques. The aims of the study were to identify the operative surgery rates in acute diverticulitis and predictors for identifying patients with complicated diverticulitis. Retrospective data collection was performed on a prospectively held database at a high-volume acute surgical unit at Logan Hospital, Queensland. Patient demographic data, disease-related factors, and treatment-related factors were collected for reporting and analysis. Over three years (2016-2018), 201 patients (64%) were admitted with uncomplicated diverticulitis and 113 patients (36%) with complicated diverticulitis. An observable downward trend was noted in the number of yearly admissions for uncomplicated diverticulitis. Complicated diverticulitis was associated with male gender ( = 0.039), increased length of hospital stay ( < 0.001), temperature ≥37.5 ( = 0.025), increased white cell count ( < 0.001), and elevated C-reactive protein ( < 0.001). Twelve patients (11%) with complicated diverticulitis initially failed conservative management. Seven patients (6%) underwent a definitive Hartmann's procedure, and 5 patients (4%) underwent percutaneous drainage of abscesses. Acute diverticulitis can be safely managed nonoperatively by medical therapy and percutaneous drainage of abscesses, with surgery reserved for patients with complicated diverticulitis with sepsis or peritonitis.