Nutrient sensing and signaling is an important area of plant biological research because of the role of plant nutrition in crop production and the constraints that nutrient limitations put on plant growth and optimal yields.The increasing cost,the limited supplies,and the negative impacts of excess application of fertilizer on the environment have all led to more research into understanding how plants acquire,sense,and utilize nutrients.Approximately two and a half years ago,Molecular Plant published a special issue (March 2010) with a series of review articles and original research papers on nutrient sensing and signaling.Many reviews have appeared and provide excellent summaries for research advances in this area (Ho and Tsay,2010;Krouk et al.,2010a;Chiou and Lin,2011;Gutierrez,2012).This highlight updates readers on some of the advances and emerging themes in this field of research since the special issue.