Evaluation of Modified Alvarado Scoring System (MASS) in the diagnosis of acute appendicitis. This was prospective study conducted on patients in Surgical Unit, Agency Headquarter Hospital Landikotal from Jan 2002 to Dec 2002, who were admitted through emergency, out patient department with suspicion of acute appendicitis. 100 patients were examined under protocol of MASS while 85 patients were having score>7 were operated upon. Average age of the patients was about 28 years. 65 were male and 20 females. 76 patients had appendicular pathologies. Predictive value of MASS was about 89%. High value in acute appendicitis validate the use of this protocol for the diagnosis of acute appendicitis.