Developing cities are experiencing substantial gaps in urban planning. They are due to approaches and instruments that do not correspond to the realities of the developing city including the prevalence of informal sector and slums, urban governance problem, and few resources. Information and communication technologies (ICTs) now offer enormous possibilities to use information flows, communication, and land-use models better. ICTs offer solutions that take greater account of informal activities, enable discussions with civil society and Internet forums to take place, etc. ICTs can enhance the planning of developing cities, if conditions are right. The chapter provides a review of the situation in developing cities. It analyses the challenges and potential of using ICTs to improve urban planning. Lastly, it puts forward key conditions for the successful and relevant implementation of ICTs in order to create the best conditions for real technological added value.