This paper discusses and evaluates use of different participatory design methods in relation to addressing the challenge of grounding imagination. It presents reflections on the use of three participatory design methods, deployed in the WorkSpace project: future laboratories, in-situ prototyping experiments and bricolage. The analysis examines how the methods differ, and how they complement one another, in relation to supporting the process of grounding imagination. The paper introduces 'future laboratories' as a participatory design method, specifically aiming at promoting interdisciplinary collaboration and grounded imagination.