Professionals and policy makers have difficulty in explaining and measuring constancy, change and differences in health, built environments and ecological conditions in cities. This is not surprising given that these are complex and multidimensional. Hence they cannot be understood only in terms of the compartmentalized knowledge of disciplinary and professional concepts and methods. The traditional roles and responsibilities of scientists, policy makers and professional practitioners ought to be reconsidered because shortcomings in both empirical research and professional practice need correcting. In contrast to conventional disciplinary approaches, inter- and trans-disciplinary contributions offer a broader intersectoral approach. These innovative approaches have been applied but they are still not mainstream in either people-environment studies, or the practice of architecture and urban planning. The contributors will share their tangible experience. They have overcome obstacles to effective implementation in the following ways: 1. By action research that transgresses conventional disciplinary silos and professional borders in order to implement inter- and trans-disciplinary contributions that tackle the complexities of urban health. 2. By participatory design processes that involve stakeholders from both the public and private sectors as well as representatives of local communities. 3. By employing innovative decision making and communication tools that promote dialogue processes that enable consensus building. This paper presents several ways and means of overcoming the barriers to applying inter- and trans-disciplinary concepts and methods that are still not mainstream. The author refers to innovative contributions in the EU-FP7 project PHENOTYPE (Positive Health Effects of the Natural Outdoor Environment in Typical Populations in Different Regions of Europe) which is being funded from January 2012 to December 2015.