Group Model Building. Graphic tools such as conceptual models open the discussion of complex systems to include people who find verbal descriptions too long and too complicated. Often a single model replaces pages of text required to describe all of the variables and their interactions (Xxxxxxxxxxxx et al., 2005, Xxxxxxxxx et al. 2007). Systems thinking methodology provides an easily accessible graphic language (variables and links between the variables are the basic elements of this language). This enables a careful and rigorous development of mutual understanding between stakeholders from diverse backgrounds and forge these diverse experiences and perspectives into a common conceptual model or family of models. Decades of group modeling experience have built a tradition of successful diagnosis and coordinated implementation of solutions of complex problems in the business world (Xxxxxxx 2000, Vennix 1996, Bertsche et al., 1996). Expanding beyond this state-of-the-art to the broader world of policy formulation and implementation at the much larger scales of society and nature has proven much more challenging. Where long-term studies or experimental manipulations in the field are not possible (as is often the case in complex ecological–economic systems) representative models can help to fill knowledge gaps (Xxxxxxxx et al., 1993). However, rare but compelling successes point toward the frontier of using systems modelling to integrate policy, science and local practice (Van den Belt (2004). These include experiments in participatory water management, amongst others in Wisconsin, USA (Xxx xxx Xxxx, et al., 2004) San Antonio Watershed in Texas, USA (Xxxxxxxx et al., 2004), Nevada (Stave 2003), Australia (Exter and Xxxxxx 2003), Poland (Xxxxxxxxxxxx et al., 2005), and Hungary (Xxxxxxxxx et al. 2008), among others. Advancing the state-of-the-art in this field requires active learning-by-doing experiments that use modelling to focus and integrate the diverse perspectives of policy makers, stakeholders and scientists.
