Positivism, post-positivism and domestic water demand: interrelating science across the paradigmatic divide Liz Sharp*, Adrian McDonald ** , Patrick Sim ** , Cathy Knamiller*, Christine Sefton* and Sam Wong   The contributions and limitations of the positivist and post-positivist approaches to research into domestic water demand are analysed and compared, and the potential for bringing the two perspectives together is evaluated. The analysis is based on a 4-year investigation of water demand conducted as part of a larger multidisciplinary research programme on sustainable urban environments and specifically the role of water in new developments. The positivist approach is more traditional and offers immediate utility in an evidence-based, legally defensible policy arena. Positivists use concepts such as good ecological status and water scarcity as measures or targets. In contrast post-positivists seek to ‘deconstruct’ concepts and decision processes in order to under- stand backgrounds, values and contexts that influence outcomes. The positivists typi- cally use large quantitative data sets and seek to establish general ‘truths’ that can be tested and used to forecast. The post-positivists undertake intensive case-study-based investigations, typically drawing on qualitative information to illustrate processes, exceptions and barriers. While each approach can add value to the other, the paper argues that the synthesis of the two approaches to create integrated interdisciplinary frameworks is unlikely to succeed. It argues that the most helpful vision is that of a pluralist research environment with ‘interrelating interdisciplinary research’ in which the relative contributions of generalisations and forecasts are discussed alongside broader interpretations about the inherent values of the current policy process. key words positivism post-positivism quantitative research interdisciplinary research water demand UK *Department of Geography and Environmental Science, University of Bradford, Bradford, West Yorkshire BD7 1DP email: e.sharp@bradford.ac.uk **Department of Geography, University of Leeds, Leeds LS2 9JT   School of Environmental Sciences, University of Liverpool, Liverpool L69 3BX revised manuscript received 29 November 2010 Introduction The major faultlines between paradigms do not lie con- veniently between the natural and social sciences but rather cut across them, dividing even those working on apparently the same problem from within the same dis- cipline. The principal relevant distinction is between positivist approaches on the one hand, characterised by a belief in an independent and objectively accessible world and by the pursuit of explanation through gen- eral laws describing regularities in nature and ⁄ or soci- ety; and a range of challenges to different philosophical and methodological elements of this position from within the social and physical sciences. (Connelly and Anderson 2007, 213) The epigraph from Connelly and Anderson (2007) highlights a fundamental schism between paradig- matically contrasting approaches to knowledge. ‘Positivist research’ studies an objective world that is Trans Inst Br Geogr NS 36 501–515 2011 ISSN 0020-2754 Ó 2011 The Authors. Transactions of the Institute of British Geographers Ó 2011 Royal Geographical Society (with the Institute of British Geographers) ransactions of the Institute of British Geographers