An overview of the mechanisms leading to the photofabrication of surface relief gratings (SRGs) on azobenzene-containing materials is presented. Emphasis is placed on the light-driven mass transport, for which theoretical models can predict a number of features of the recorded SRGs. Examples are given of recent developments in the field, with the inscription of SRGs on high molecular weight azocellulose and the use of Raman spectroscopy to investigate photodegradation in SRGs recorded on electrostatically assembled layer-by-layer films.