Williams, S.D.P.; Woodworth, P.L., and Hunter, J.R., 2016. Commentary on ‘Coastal planning should be based on proven sea level data' by A. Parker and C.D. Ollier (Ocean & Coastal Management, 124, 1–9, 2016).

A recent paper by A. Parker and C.D. Ollier (Ocean & Coastal Management, 124, 1–9, 2016), concerned with the use of ‘proven' sea-level data for coastal planning, contained a number of incorrect or misleading statements about sea-level data sets and measurement methods. In this commentary, we address aspects of sea-level records that could have been misunderstood by readers of that paper. While we agree with the main point made by the authors, that the best possible sea-level data are required by coastal planners, we suggest that planners should base their work on wider and better informed sources of sea-level information.