Xylem tissues serve an important dual role during growth and development of plants as they are required for both physical support and transport of water from root to shoot tissues. During growth, plants modulate xylem characteristics such as size and numbers to cope with changing environmental conditions such as drought stress. Hence, the molecular mechanisms underlying these responses are important targets for crop breeding or editing efforts. However, not much is known about the early stages of xylem development where these important xylem characteristics are laid down. The main aim of this research proposal is to identify and characterize molecular regulators of early xylem development by i) mapping the gradual transcriptional changes at single cell resolution by constructing and validating developmental trajectories, ii) identifying novel regulators of xylem development by inferring and validating Gene Regulatory Networks, and iii) functionally characterizing these novel early xylem regulators in detail. The outcomes of this research proposal will not only shed light on early xylem development by identifying and characterizing novel regulators; but will also function as a starting point for applied research projects, that use these regulators to optimise plant growth in a changing environment.