What forms of animal life take hold in cities, and how might we engage in probiotic urban practices to enhance such life?  In this edited volume, we explore how urban residents from varied species relate to their surrounding landscapes and to each other, and how human understandings of such entanglements might make us better companions to our co-inhabitants through policy, planning, design, and other spatial practices.  While the framework of the book draws on urban theory, animal studies,  and political ecology, we are interested in the details of animal life from individuals to groups to species, as well as in their myriad interactions.