We will conduct a workshop to accelerate the maturation of the discipline of Urban Ecology. The workshop will assess the current state of knowledge concerning the ecology of cities, and synthesize this information for researchers, resource managers, and policy makers. The workshop will also identify new or critically needed research directions. Working groups in discussion sessions will be tasked with identifying and synthesizing sets of hypotheses, needs and approaches to guide future ecological research in urban and urbanizing landscapes. The value of initiating comparative studies of cities within and across nations, and developing standardized methods to facilitate comparisons, will be among those approaches considered. Since urban ecosystems differ from other ecosystems in being inhabited by people, human occupation and management directly and indirectly drive ecological structure and processes in cities. Therefore, one of the overarching goals of the workshop will be to identify how to proceed so as to determine the effects of differing geographic, environmental and socio-economic contexts on species populations, biological communities and ecosystem processes. Feedbacks between natural, built and human components of these ecosystems that influence quality of life for people will also be explored. Workshop groups will explicitly consider means of deepening our scientific understanding of human decision-making processes across multiple social scales and their influences on the spatio-temporal dynamics of ecological heterogeneity. Developing such a synthesis and providing a road map for future research will contribute to making urban ecology a more predictive science, and provide a foundation for more science-based policymaking and land-use planning in urban and urbanizing landscapes in the future.