This article provides an English translation of an unpublished German typescript found in the archive of the architect Julius Posener in the Akademie der Kunst, Berlin. Posener, a professor of architectural history at the Hochschule für Bildende Künste (HBK), travelled with a colleague and fifteen students to England for a fortnight in March 1963. They met several prominent architects, saw a wide selection of their current and recently completed works, and attended events at the Architectural Association school. The typescript is an account of the trip that he wrote up from notes in his diary on 29 March, two days after their return. Posener, who had previously spent almost a decade teaching architecture in London, proves to have been a sympathetic observer of the scene, eager to compare and contrast what he saw in England with contemporary work in Germany; his account evokes subtle disagreements between himself and his colleague on conceptual and historical points, and gives us an insight into the day-to-day workings of Denys Lasdun’s office, the Architectural Association, the London County Council, and the Building Research Station in Garston.