Fruits and vegetables are essential components of a healthy, balanced diet, as they provide nutrients, vitamins, minerals and fibre. They are integral to the recommendation by the World Health Organisation to eat 5 portions a day. It is important therefore, to produce fruits and vegetables that have high levels of these beneficial compounds, as well as them having a pleasing taste and appearance. In order to do this, we must understand the molecular events that occur during fruit and vegetables development and ripening, as well as minimising deleterious changes from harvesting, stress and storage. This chapter describes our current understanding of these processes in terms of the changes to the proteome and individual proteins that have been identified using mass spectrometry. This knowledge will enable plant breeders to optimise the dietary value of crops and minimise losses to yields through stress and storage.