The complexity of the environment and ongoing, often unpredictable environmental and social responses to policy means that policy becomes continual experimentation with limited repeatability and replication (Folke et al., 2005; Pahl-Wostl, 2009). In response, the integration of knowledge from different sources and types is often advocated (see Nursey-Bray et al., 2014; Raymond et al., 2010; van der Molen et al., 2016 as recent examples), as is ongoing learning (see Folke et al., 2005; Pahl-Wostl, 2009). Adaptive management, with its participatory processes and knowledge discovery focus, is now widely accepted as a necessity in environmental management (Allan, 2009; PahlWostl, 2009; Pahl-Wostl et al., 2013). Adaptive management gathers knowledge from across an environment’s stakeholders to plan for experimentation as part of policy development (Walters and Holling, 1990); applying a paradigm of scientific problem solving within the policy process. Despite widespread support for adaptive management, examples of successful adaptive management have remained scarce (Eberhard et al., 2009; Wilhere, 2002; Allen and Gunderson, 2011). Challenges with stakeholder engagement and acceptance of results, the complexity of the science and resourcing issues, both time and funding have been noted elsewhere (Allen and Gunderson, 2011). It has been suggested that legislated prescription of adaptive management is needed to overcome these challenges and ensure it actually occurs (Lee, 1993). In 2012 adaptive management became a defined term in Australian water legislation in the Murray-Darling Basin Plan (Commonwealth of Australia, 2012), providing a fit case to test these arguments for prescription in legislation. First, a brief literature review of adaptive management and evaluation is provided, followed by a description of the method used and an introduction to the case. Legislation, policy documentation and semi-structured interviews are analysed to determine the social construction of adaptive management by government. The results demonstrate that the true barrier to adaptive management is not the absence of legal requirement, but conflation of adaptive management with evaluation. The implications to water reform and more broadly, the role of science in policy are discussed.