Some appreciations about urban sustainability measurement using indicators are shown in this document, which also proposes the Theory of Global Change Syndromes developed by the German Advisory Council on Global Change (WBGU) and adapted by Swiss National Centre of Competence in Research North-South (NCCR N-S), as a valuable tool for creating systemic indicators that can address urban problems comprehensively. Finally, it explains with The Favela Syndrome Intensity example, the way that NCCR N-S uses to create an applicable indicator in the context of developing countries, and it suggests some complements to cover as many aspects that facilitate the state assessment of problems related with unplanned and informal urbanization.