Fruit quality at harvest is a complex trait, including size, overall flavour (taste and texture) and visual attractiveness (colour, shape), which depend on both genotype and environment. The improvement of fresh product quality is slowed down by this complexity. It is expected that the development of process-based models and their integration in ecophysiological models should facilitate quality management, provided that integration properly accounts for interactions among biological processes. Here we describe some process-based models developed on peach and tomato fruits, which predict final fruit size and composition in primary compounds. Perspectives of integration of such models are discussed.