This article provides an overview on different types of managing interdisciplinary knowledge integration in environmental urban research projects: 1. "synthesis-then", 2. "synthesis-online", 3. "synthesis-first", 4. "synthesis-as contracted". We present two projects in the context of urban ecology, in order to discuss two types of integration management in more detail. In the "synthesis-first" type of project management, interdisciplinary knowledge integration is organized through "syntheses groups" that represent the relevant perspectives on a case. We introduce "synthesis-first" using the Zurich North case study as an example. In the "synthesis-online" type of project management, interdisciplinary knowledge integration is wanted but occurs only occasionally. As an example, we present the interdisciplinary Berlin project on urban ecology. This article argues that knowledge integration in general requires sufficient management and an audience for the products of knowledge integration (scientific or not). We emphasize the importance of "boundary objects" for interdisciplinary knowledge integration in general and for urban ecology in particular.