Gavin lectures for numerous artistic, musical and literary institutions and festivals worldwide.

He has given talks for the Royal Opera House, the National Trust, the Cheltenham Literature Festival, the National Theatre, the BFI, Southbank Centre, the Philharmonia, the Oxford Lieder Festival, the Bamberg Biennale, WNO, the CBSO, the LSO, ENO, Garsington, Glyndebourne, the BBC Proms, the BBC Scottish Symphony Orchestra and the Austrian Cultural Forum, as well as for the UK Jewish Film Festival, the Freud Museum in London and the Art Fund.

Gavin has also been invited to speak at various prominent exhibitions, including at the British Museum (Germany: Memories of a Nation), the National Gallery (Facing the Modern: the Portrait in Vienna 1900 and Delacroix and the Rise of Modern Art), the Royal Academy (Klimt/Schiele), the Neue Galerie in New York (Vienna 1900: Style and Identity), the V&A (Diaghilev and the Ballets Russes), Tate Britain (Hogarth) and Tate Liverpool (Gustav Klimt: Painting, Design and Modern Life in Vienna 1900).

Gavin is an accredited lecturer for The Arts Society (formerly NADFAS), speaking at societies throughout the United Kingdom, as well as in Spain, Belgium, the Netherlands and New Zealand.