S Ayyar, born on March 10, 1950, is a retired Indian Administrative Service officer from the 1989 batch, Tamil Nadu cadre. Throughout his career, he held various positions including Sub Collector, Special Officer, District Collector, Director, Managing Director, Project Director, Commissioner, and Joint Secretary. His most recent role was Joint Secretary from November 4, 2008, to March 31, 2010. Mr. Ayyar served with distinction across multiple administrative capacities before retiring from service.