This thesis explores how the structure (urban alphabet) of the ABC suburban model could evolve and transform in order to achieve a more sustainable future suburb. In particular, the “ABC city” was introduced in Stockholm’s General Plan of 1952 as a prototype for the suburban development of the municipality with Vällingby to be the first area developed according to this idea. So, it is examined how this first ABC suburb, Vällingby, could be reformed almost 100 years after its inauguration in order to consist a prototype for the future restructure of ABC suburbs. Subsequently, the project is articulated in 3 different time frames a)Past, b)Present and c)Future that seek to explore the structure of the ABC suburban model, its evolution until nowadays and its future development.