Mark Textor presents a critical study of the work of Franz Brentano, one of the most important thinkers of the 19th century. His work has influenced analytic philosophers like Russell as well as phenomenologists like Husserl and Sartre, and continues to shape debates in the philosophy of mind. Brentano made intentionality a central topic in the philosophy of mind by proposing that 'directedness' is the distinctive feature of the mental.