Ingemar Lindh's work on the principles of collective improvisation has crucial implications for the history of twentieth-century laboratory theatre. His early work with Étienne Decroux and Jerzy Grotowski contributed to the development of a unique practice that resists directorial montage, fixed scores, and choreography; and the ethical dimension that accompanies Lindh's research on collective improvisation is illuminating for a more holistic understanding of the technical and aesthetic considerations in theatre. In this article, Frank Camilleri discusses some of the key aspects of this dimension, notably the dynamics of hospitality and encounter that inform Lindh's approach and the question of responsibility in the actor's work. Frank Camilleri is Lecturer in Drama and Theatre Studies at the University of Kent. From 2004 to 2008 he was Academic Coordinator of Theatre Studies at the University of Malta. He is also Artistic Director of Icarus Performance Project – an ongoing research laboratory that investigates the intermediary space between training and performance processes. Camilleri's work with Lindh in the mid-1990s was instrumental for the development of this research practice.