Research in the Fitzpatrick team centres around unravelling the molecular aspects of B vitamin metabolic pathways in plants, the primary source of these compounds in the human diet. We strive to decipher the pathways of how, when and where plants make these vitamins de novo, interconvert different chemical forms through salvage and recycling, transport and deliver to cellular factors such as enzymes requiring them for action. We use genetic, cell biology, biochemistry and physiology approaches to decipher the dynamic molecular mechanisms (which can be a function of the environment) and architecture of the complex protein machineries. We mainly use the model plant Arabidopsis and are currently implementing Lotus. These activities allow us to showcase the importance of these pathways for plant growth and development, as well as homeostasis depending on the environment. We have been able to characterize links with carbon/nitrogen balance, the circadian clock and response to abiotic stresses such as heat, overuse of nitrogen fertilizer as well as elevated carbon dioxide. Acquiring such knowledge leads us to biotechnological approaches to enhance the nutrient content of selected crop plants that may additionally enhance tolerance to environmental perturbances. Our main crop plant of choice is rice as the consumed grain is poor in micronutrient content, particularly after processing. So far, we have successfully enhanced the vitamin B1 content in rice endosperm, i.e. the polished grain, that would reach approximately one third of the recommended daily intake in a single serving. Most importantly, these crop lines were grown and monitored in the field over several generations and there was no impact on agronomic traits or yield. The knowledge generated also led to the successful enhancement of the vitamin B6 content of cassava storage roots such that a single serving of the cooked product would reach the recommended daily intake.