I am professor of theoretical philosophy at Freie Universität Berlin, and co-director of the "Human Abilities" project (www.human-abilities.de). Most of my work focusses on the metaphysics and epistemology of modal properties - dispositions, abilities, and so on - and their role in the metaphysics and epistemology of modality. I am currently working on a book that develops an agency-based approach to the epistemology of modality.