title: Orbital angular momentum: a personal memoir.
abstract: A definitive statement of the model used to describe orbital angular momentum is essentially now available. Its early history, and the interaction of those who played key roles in its development over 20 years ago in its development, is outlined in this Memoir.This article is part of the themed issue 'Optical orbital angular momentum'.
authors.affiliation: SUPA and Department of Physics, University of Strathclyde, Glasgow G4 0NG, UK stephen.barnett@glasgow.ac.uk.
authors.forename: L
authors.initials: L
authors.lastname: Allen
keywords: angular momentum; laser physics; optics