This review by Sjef Smeekens provides an overview of the mechanisms of sugar sensing and signal transduction in plants, highlighting the importance of sugars throughout the plant's life cycle. The review discusses the different systems for sensing hexoses and sucrose, including hexokinase-dependent and -independent pathways. It also covers the role of the SNF1 kinase complex and the regulatory PRL1 protein in signal transduction. The impact of sugar signaling on seed development and germination is explored, particularly the mechanisms by which sugar signaling controls gene expression. The review further examines the interaction of sugar signaling with other pathways, such as ethylene and ABA signaling. Experimental approaches, including genetic, molecular, biochemical, and physiological methods, are discussed to understand sugar sensing and signaling in plants. The review emphasizes the complex regulatory networks involved in sugar signaling and the importance of these pathways in plant physiology and development.This review by Sjef Smeekens provides an overview of the mechanisms of sugar sensing and signal transduction in plants, highlighting the importance of sugars throughout the plant's life cycle. The review discusses the different systems for sensing hexoses and sucrose, including hexokinase-dependent and -independent pathways. It also covers the role of the SNF1 kinase complex and the regulatory PRL1 protein in signal transduction. The impact of sugar signaling on seed development and germination is explored, particularly the mechanisms by which sugar signaling controls gene expression. The review further examines the interaction of sugar signaling with other pathways, such as ethylene and ABA signaling. Experimental approaches, including genetic, molecular, biochemical, and physiological methods, are discussed to understand sugar sensing and signaling in plants. The review emphasizes the complex regulatory networks involved in sugar signaling and the importance of these pathways in plant physiology and development.