Linking urban sustainability transitions and ecosystem services, Pincetl described how cities changed since the 19th century, following the modernist sanitary city idea, and then since the 1970s how cities further evolved to incorporate the new environmentalist approach. The above well describes what happened in the Western world, but cities in Central and Eastern Europe (CEE) partly followed a different transition path. As a result, CEE cities may finally enter a delayed sustainability transition. However, they still face many challenges, such as urban sprawl and the sealing of surfaces due to the development of new infrastructure. To study the above processes, the author of this chapter follows the approach of social-ecological transitions. This approach highlights that whatever change they address, it boils down to changes in complex and coevolving social and ecological systems. Interestingly, ecological issues have been left out of sustainability transitions research carried out so far, except for specific environmental challenges, such as climate change, water and waste management.