Hypothesis: Outcomes of laparoscopic appendectomy (LA) will be similar to open appendectomy (OA) in children of all ages. Design: Retrospective cohort study using discharge abstract data. Setting: Twelve regional hospitals in Southern California. Patients: Seven thousand six hundred fifty patients underwent appendectomy for acute appendicitis (LA=3551, OA=4099). Intervention: Laparoscopic appendectomy or OA. Main Outcome Measures: Thirty-day morbidity (wound infection, abscess drainage, and readmission) and length of hospitalization. Results: Use of laparoscopy increased from 22% in 1998 to 70% in 2007. Overall, patients undergoing LA were older (mean [SD] age, 12.8 [3.2] vs 10.4 [3.7] years; P<.001) and had a lower perforation rate (24% vs 34%; P<.001). Multivariable logistic regression demonstrated a decreased odds ratio for wound infection (odds ratio, 0.6; 95% confidence interval, 0.5-0.8) and abscess drainage (odds ratio, 0.6; 95% confidence interval, 0.4-0.7) following LA compared with OA. Multivariable linear regression also showed decreased length of hospitalization following LA compared with OA. Conclusion: Now the preferred operation for children with appendicitis, LA was associated with a decreased risk of wound infection, abscess drainage, and length of hospitalization compared with OA.