Recent progress on the late-stage C–H functionalisation of peptides will be presented. While C–H functionalisation of amino acids employing installed ‘directing groups’ has been developed as a valuable method for preparation of non-natural amino acids in recent decades, elaboration of C–H functionalisation strategies to peptides and proteins is limited by poor selectivity in molecules containing multiple amide groups. We have developed a new directing group that can be incorporated into a peptide backbone to facilitate the site-selective and traceless C–H functionalisation of peptides. This directing group can subsequently be transformed back to a native amide bond, thus allowing the traceless preparation of complex peptides possessing a native backbone.