John Batty, BSc (Hons) is a chemist with over 40 years of experience in the water industry with particular emphasis on water quality, pollution prevention and control and dangerous substances. He is now an independent consultant and an Associate of wca after spending the bulk of his career in the public sector where for the last ten years he has been the UK technical expert for priority substances under the Water Framework Directive. He was responsible for negotiating several directives on behalf of the UK including the 2008 EQS Directive. He was co-chair of the EU Expert Group on Review that undertook much of the preparatory development work for the recent EU proposal on priority substances and was the editor for the EU Common Implementation Strategy Guidance on Mixing Zones.