Abstract The delineation of capture zones and the subsequent designation of protection zones around groundwater sources is a key element of the Environment Agency ‘Policy and Practice for the Protection of Groundwater’. The protection principles apply to all sources, but priority in defining protection zones has been afforded hitherto to the major public supply sources. The EA recognizes the need to have available a methodology for establishing protection zones around the smaller sources, of which there are upwards of 76 000 in England and Wales, compared with some 4000 larger sources used principally for public water supply. The delineation of capture zones around the smaller sources presents a number of technical and practical problems which tend not to arise when carrying out such procedures for the larger sources. This paper reviews the methods for delineating groundwater source capture zones which are readily available; it discusses the practical issues associated with the application of these methods to the smaller sources, and presents recommendations for their use in a range of hydrogeological settings.