Flame spread underpins a huge range of fire problems and encompasses some of the most complex aspects of fire science including strong coupling between gas and solid phase phenomena. Although there are many approaches to predict or model flame spread behaviour, many of these rely on empirical data and cannot be relied on in predictive capacity. However, these models date from a time when the objectives of fire science were different from today with a strong emphasis on developing standardised testing methods and providing information to first responders. Advances in diagnostics and modelling in recent years along with changes in the needs of users of fire safety science means that there are significant new opportunities, and benefits, to enhancing our understanding of flame spread. These will be explored in this talk with emphasis given to furthering understanding of the fundamental processes underpinning flame spread, the challenges of the applications of flame spread and the tools that we might be able to adopt to answer these questions.