This review discusses the WRKY transcription factors, a large family of proteins that play crucial roles in plant development and response to environmental stimuli. WRKY proteins are characterized by a conserved DNA-binding domain, the WRKY domain, which includes the sequence motif WRKY and a zinc-finger motif. These proteins have evolved from early eukaryotes and are highly diversified in plants, with over 90 members in rice and 74 in Arabidopsis. The review highlights recent advances in understanding the functions of WRKY proteins, particularly their roles in defense signaling and developmental processes. In defense signaling, WRKY factors are involved in coordinating responses to biotic and abiotic stresses. They interact with mitogen-activated protein kinases (MAPKs) and other signaling molecules to regulate gene expression. For example, specific WRKY proteins, such as ΔWRKY22 and ΔWRKY29, are essential for resistance to bacterial and fungal pathogens. In development, WRKY genes are involved in various processes, including trichome development, hormone signaling, and fruit maturation. The review also discusses the challenges in defining the in vivo functions of individual WRKY genes, noting that traditional genetic approaches have had limited success in uncovering specific functions. Techniques like chromatin immunoprecipitation (ChIP) and global expression arrays are being used to better understand the interactions and target genes of WRKY factors. The authors conclude that the expansion of the WRKY gene family in plants is likely a response to environmental pressures, particularly from pathogens. Further research is needed to identify interacting proteins and to understand the combinatorial gene expression programs regulated by WRKY factors. Structural studies at atomic resolution will also be essential to fully appreciate how these factors modulate transcription.This review discusses the WRKY transcription factors, a large family of proteins that play crucial roles in plant development and response to environmental stimuli. WRKY proteins are characterized by a conserved DNA-binding domain, the WRKY domain, which includes the sequence motif WRKY and a zinc-finger motif. These proteins have evolved from early eukaryotes and are highly diversified in plants, with over 90 members in rice and 74 in Arabidopsis. The review highlights recent advances in understanding the functions of WRKY proteins, particularly their roles in defense signaling and developmental processes. In defense signaling, WRKY factors are involved in coordinating responses to biotic and abiotic stresses. They interact with mitogen-activated protein kinases (MAPKs) and other signaling molecules to regulate gene expression. For example, specific WRKY proteins, such as ΔWRKY22 and ΔWRKY29, are essential for resistance to bacterial and fungal pathogens. In development, WRKY genes are involved in various processes, including trichome development, hormone signaling, and fruit maturation. The review also discusses the challenges in defining the in vivo functions of individual WRKY genes, noting that traditional genetic approaches have had limited success in uncovering specific functions. Techniques like chromatin immunoprecipitation (ChIP) and global expression arrays are being used to better understand the interactions and target genes of WRKY factors. The authors conclude that the expansion of the WRKY gene family in plants is likely a response to environmental pressures, particularly from pathogens. Further research is needed to identify interacting proteins and to understand the combinatorial gene expression programs regulated by WRKY factors. Structural studies at atomic resolution will also be essential to fully appreciate how these factors modulate transcription.