14-3-3 proteins are phosphoserine-binding proteins that regulate the activities of a wide array of targets via direct protein–protein interactions. In animal cells, the majority of their known targets are involved in signal transduction and transcription. In plants, we know about them primarily through their regulation of the plasma membrane H+-ATPase and enzymes of carbon and nitrogen metabolism. Nevertheless, an increasing number of plant signalling proteins are now being recognized as 14-3-3-interacting proteins. Plant 14-3-3 proteins bind a range of transcription factors and other signalling proteins, and have roles regulating plant development and stress responses. Important mechanisms of regulation by 14-3-3 include shuttling proteins between different cellular locations and acting as scaffolds for the assembly of larger signalling complexes.