The article reviews significant progress in understanding the coupling of folding and binding processes involving intrinsically disordered proteins (IDPs). IDPs, which are often associated with cellular control mechanisms and signaling, have been identified at the center of protein interaction networks. The review highlights technical advances in characterizing IDPs, including the use of spectroscopic methods and computational tools. It discusses the molecular principles and interactions involved in the coupled folding and binding of IDPs, emphasizing the role of hydrophobic interactions and the formation of molecular recognition elements (MoREs). The mechanism of coupled folding and binding is explored, with a focus on induced folding and conformational selection. The kinetics of these processes and the cooperative binding of IDPs to their targets are also examined. The article concludes by discussing the role of phosphorylation and flexibility in signal transduction and the challenges of studying IDPs in vivo.The article reviews significant progress in understanding the coupling of folding and binding processes involving intrinsically disordered proteins (IDPs). IDPs, which are often associated with cellular control mechanisms and signaling, have been identified at the center of protein interaction networks. The review highlights technical advances in characterizing IDPs, including the use of spectroscopic methods and computational tools. It discusses the molecular principles and interactions involved in the coupled folding and binding of IDPs, emphasizing the role of hydrophobic interactions and the formation of molecular recognition elements (MoREs). The mechanism of coupled folding and binding is explored, with a focus on induced folding and conformational selection. The kinetics of these processes and the cooperative binding of IDPs to their targets are also examined. The article concludes by discussing the role of phosphorylation and flexibility in signal transduction and the challenges of studying IDPs in vivo.