Portrait of Leon Fields

Leon Fields : Senior Consultant

Leon’s areas of expertise include market design, competition policy and the economic regulation of utilities. He is a member of the Regulation, Water and Competition teams at Oxera, and has particular expertise in incentive regulation, behavioural economics and industrial organisation. He is a member of the Agenda in focus board.

Leon has in-depth knowledge of the water sector, having been actively involved in all aspects of the 1999, 2004, 2009, 2014 and 2019 periodic reviews. Across utility sectors, he has detailed knowledge of incentive regulation, regulatory reform and market reform. He has worked for several small-island jurisdictions on regulatory change.
Leon has also undertaken a number of projects on consumer behaviour, firm behaviour and market design. He is an expert in water tariff design, and in how the objectives of cost recovery, efficiency and compliance can be balanced. He has also undertaken water infrastructure option appraisal for a variety of clients.

Leon speaks English.

Tel: +44 (0) 1865 253014

Leon's specialisms include:

professional experience

  • Leading and providing economic regulation training to South West Water (2020)
    Advice to SHE-T (UK) on an assessment framework for its Consumer Value Proposition (2019–20)

  • Advice to SHE-T (UK) on an assessment framework for its Consumer Value Proposition (2019–20)

  • Leading advice to ComReg (Ireland) on setting financial penalties for breaches of regulatory obligations in telecoms (2016–20)

  • Presented to the First European Forum on the Regulation of Water Services (EFRWS) on tariff design and water efficiency (December 2019)

  • Project manager in advice to Águas de Portugal on potential regulatory reforms (January–March 2019)

  • Expert witness, appointed by Manchester Ship Canal Company, on scheme selection and funding in the water sector (2017–18)


  • Niels, G., Dijk, R. van and Fields, L. (2013), ‘Behavioural economics and its impact on competition policy: A practical assessment’, Competition Law Journal, 12:3, pp. 374–84.

  • Fields, L., Horncastle, A. and Noble, R. (2009), ‘Water competition and the Cave Review: a clear way forward?’, Competition Law Journal, 8:3, pp. 238–47.


  • MSc Economics, University of Warwick

  • BSc Economics, University of Warwick

Latest Insights:  Leon Fields

A large body of academic literature has sought to explain why members of observably different groups fare so differently in the labour market. Theories of distaste towards certain groups, alongside…
Recent developments in neuroscience show that decision-making is more complex than the (basic) model of System 1 and System 2 that was formulated for use in behavioural economics by the…
How should penalties be set so as to punish breaches of rules while deterring any future breaches? Oxera provided advice to the Irish Commission for Communications Regulation (ComReg) on how…
In May 2021, Ofwat, the economic regulator of the water industry in England and Wales, set out its vision for the next price review (PR24). Key themes are long-term planning,…