He trained many national team members and champions from the 1940s through the 1980s, teaching champions and prominent fencers including George Worth, Tibor Nyilas, George Kolombatovich, Allan Kwartler, Neil Lazar, Uriah Jones, Robert Russell, Anne O'Donnell Russell, Marty Lang, Denise O'Connor, Ed Ballinger, Israel Colon, Ernest Schmatolla, Maurice Kamhi, Andy Shaw, Ed Wright, and many others.

Others who fenced at Salle Santelli included Olympians Norman Lewis, Robert Blum, Ralph Goldstein, Albert Axelrod, and Zaddick Longenbach.

Santelli tirelessly and generously promoted fencing in all aspects, including stage choreography on Broadway (in productions of Hamlet, Romeo and Juliet, Peter Pan and many others) and providing free instruction to high school fencers.

Giorgio generously supported fencing masters coming to the United States, giving them a place to teach until they established their own schools, including great maestros such as Csaba Elthes.

Santelli made a unique contribution by tearing down the color barrier that existed in what had been a patrician sport, inviting black fencers to his club at a time when fencing had been a segregated activity, and producing Olympians and national champions such as Uriah Jones, Ed Ballinger, and Ed Wright.