The present new approach to building nanocrystals of materials with more complex crystal structures is based on the concept of progressive condensation of an intermediate structural unit. A simple method to control the growth of TiO2 nanocrystallites and the formation of nanostructured TiO2-based materials is presented. The method used to form these materials is based on controlling the hydrolysis and polycondensation of titanium alcoxide using organic ligands in order to build and stabilize intermediate building units (slabs). TiO2 particles with different sizes and shapes are obtained, simply by changing the titanium/cation ratio, and exhibit the anatase crystal structure. The small clusters formed condense, leading to well-defined nanocrystallites, which in turn self-assemble into superlattices.