AbstractData are presented on the position of the equilibria of cyclo(Xxx‐Pro‐Yyy)2 backbones between forms with two cis Xxx‐Pro peptide bonds and forms with only trans peptide bonds. These data are interpreted in terms of two factors: a solvent‐independent steric interaction between the Xxx and Pro side chains, and the ability of solvent to influence the transannular electrostatic interaction between NH and CO groups of the Xxx units in the all‐trans form.