Chapter I. Intentionality, mentalism and the problem of objective reference. 1.Introduction: intentionality and the denial of mentalism/ 2.Brentano's thesis of intentionality/ 3.The linguistic re-formulation of Brentano's thesis of intentionality: new criteria and concerns/ 4.Advantages of the linguistic version of the intentionality thesis/ Chapter II. Sense, reference and semantical frameworks. 1.Frege's theory of sense/ 2.Russell's theory of names/ 3.Conclusion/ Chapter III. Intentionality, relations and objects. I: The relational theory. 1.Introduction/ 2.Belief as a relation/ 3."Objects" of thought/ 4.Conclusion/ Chapter IV. Intentionality, relations and objects. II: The irreducibility theory. 1.Introduction/ 2.Anscombe's theory of intentional objects/ 3.The intentionality of perception/ 4.Perception and its puzzles/ 5.Concluding remarks/ Chapter V. Sense and the psychological. 1.Introduction/ 2.Intensions and mental entities/ 3.Sense and psychologism/ 4.Varieties of mentalism/ Chapter VI. Intentionality: the vehicle of objective reference. 1.Introduction/ 2.Husserl's theory of intentionality: the Fregean connection .....