The article presents Frege’s distinction between Sense and Reference. After a short introduction, it explains the puzzle which gave rise to the distinction; Frege’s earlier solution, and his reasons for its later repudiation. The distinction, which embodies Frege’s second solution, is then discussed in two phases. The first, which is restricted to proper names, sets out its most basic features. The second discusses ‘empty’ names; indirect speech, and the distinction for predicates and for complete sentences. Finally, two criticisms, by Russell and by Kripke, are briefly set out.