Over the course of forty-eight years at the Neighborhood Playhouse, Meisner honed his skills as an acting instructor. Growing out of the days with the Group Theatre and the Russian theater theorist Constantin Stanislavsky, Meisner created a series of exercises for actors. For Meisner, acting was about reproducing honest emotional human reactions. He felt the actor's job was simply to prepare for an experiment that would take place on stage. The best acting, he believed, was made up of spontaneous responses to the actor's immediate surroundings. Meisner explained that his approach was designed "to eliminate all intellectuality from the actor's instrument and to make him a spontaneous responder to where he is, what is happening to him, what is being done to him."

Meisner's role within the theater community remained important throughout his long career. Among his famous students were actors Gregory Peck, Robert Duvall, Grace Kelly, Diane Keaton, Steve McQueen, James Caan, Joanne Woodward, Lee Grant, Dylan Mcdermott, Sydney Pollack and Peter Falk. Gregory Peck said of Meisner, "What he wanted from you was truthful acting...He was able to communicate, and the proof of that is the number of people that have come out of [the Neighborhood Playhouse] over a forty-year period who've gone on to become people who set standards of acting." Though troubled with a number of physical problems, including losing his larynx, Meisner continued to be an active part of the theater community for his entire life. During his final years, he split his time between the Caribbean island Bequia and New York. He died at age 91, leaving behind a legacy of commitment and enthusiasm rarely seen in any art.

Take it from a director: if you get an actor that Sandy Meisner has trained, you've been blessed." - Elia Kazan