Stanislavski's work made little impact on British theatre before the 1960s. Joan Littlewood and Ewan MacColl were the first to introduce Stanislavski's techniques there. In their Theatre Workshop, the experimental studio that they founded together, Littlewood used improvisation as a means to explore character and situation and insisted that her actors define their character's behaviour in terms of a sequence of tasks. The actor Michael Redgrave was also an early advocate of Stanislavski's approach in Britain. The first drama school in the country to teach an approach to acting based on Stanislavski's system and its American derivatives was Drama Centre London, where it is still taught today.