Many of the properties exhibited by separation membranes are due to interactions at the interface with their environment, including flux, rejection of solutes and surface fouling. As such when trying to understand how such interactions affect their function and when developing novel membranes with improved properties, a thorough understanding of their surface properties is essential. In this review paper we describe and discuss a number of instrumental techniques commonly used to characterize membrane surface, along with illustrative examples from the literature on membrane development and characterisation. The techniques described indude spectroscopic techniques, microscopic techniques and methods to measure the surface wettability and electrokinetic behaviour. (C) 2017 Elsevier B.V. All rights reserved.