AbstractA general study on the β‐cis‐elimination mechanism was made, concentrating on the steric requirements of the reaction and the influence of substituents in the alkyl (especially the β‐position) and in the acid moieties. Kinetic data on cycloalkyl esters ‐ mainly substituted cyclohexyl acetates ‐ show that a planar transition state, if not essential, is highly preferred. Polar substituent effects (β‐alkyl, ‐chloro, ‐acetoxy and ‐acetyl) in the alkyl moiety, being relatively small as such, are found to be coupled with those of other structural variations, especially in the case of β‐acetyl derivatives.Mechanistic implications are discussed in detail, leading to a transition state description comparable with that of solvolytic elimination reactions: a range of structures – in this case of a strongly concerted character – intermediate between carbonium ion