Lionel Robbins (1898-1984) is best known to economists for his Essay on the Nature and Significance of Economic Science (1932 and 1935). To the wider public he is well known for the 'Robbins Report' of the 1960s on Higher Education, which recommended a major expansion of university education in Britain. However, throughout his academic career - at Oxford and the London School of Economics in the 1920s, and as Professor of Economics at the School from 1929 to 1961 - he was renowned as an exceptionally gifted teacher. Generations of students remember his lectures for their clarity and comprehensiveness and for his infectious enthusiasm for his subject. Besides his famous graduate seminar his most important and influential courses at LSE were the Principles of Economic Analysis, which he gave in the 1930s and again in the late 1940s and 1950s, as well as the History of Economic Thought, from 1953 until long after his official retirement. This book publishes for the first time