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Protein homeostasis relies on chaperones such as HSP70 and HSP90, which assist in the folding, activation, and turnover of client proteins. Their activity is modulated by co-chaperones, many of which contain tetratricopeptide repeat (TPR) domains. A subset of these, known as carboxylate clamp TPR (CC-TPR) domains, possess distinctive structural features that mediate interactions with the chaperones' C-terminal EEVD motifs. This review focuses on plant TPR-containing co-chaperones, particularly those with CC-TPR domains, because they provide the structural basis for selective HSP70 and HSP90 recognition -a central but understudied aspect of plant proteostasis. We summarize advances in understanding the structure and diversity of plant TPR co-chaperones, and discuss three representative examples: AtRPAP3, a component of the R2T complex; HOP, a co-chaperone integrating hormonal and stress responses; and SGT1, a TPR protein that interacts with HSP90 through a TPR-independent mechanism and is crucial for immunity and development. Comparative evidence reveals both conservation and plant-specific diversification of TPR co-chaperone function, reflecting their adaptation to environmental and developmental cues. We conclude that plant TPR proteins constitute a versatile regulatory layer that coordinates chaperone activity across multiple cellular processes. Understanding their mechanisms will be essential to map the chaperone networks that underpin plant resilience and growth.