Nitrogen is a critical macronutrient with a major influence on wheat grain yield and end-use quality. The key challenges are to detect and use genetic variability to breed for more efficient wheat varieties. For this, traits related to nitrogen capture by the root system, then nitrogen assimilation and finally nitrogen remobilization from source organs to the grain are to be considered. The possibility of using these traits will depend on the available genetic variability and the identification of molecular markers associated with relevant chromosomal regions. Future major research trends include the developments in high-throughput phenotyping and characterization of the response to combinations of environmental factors.