Stoddart Group Celebrates 50th Anniversary of Supramolecular Chemistry with Chemical Society Reviews Cover - Macrocycles are molecular entities that display a combination of molecular recognition and complexation properties with vital implications for host–guest/supramolecular chemistry. In 1967, Charles J. Pedersen published a communication and a full article in J. Am. Chem. Soc. which were the first reports of the synthesis and the alkali metal ion complexation properties of crown ethers. 2017 marks the 50th anniversary of this seminal work. A survey on recent developments of the chemistry of naturally occurring cyclodextrins, along with a variety of synthetic flexible and rigid macrocycles — that have drawn their inspiration from Pedersen’s landmark discovery of crown ethers — is described in Chemical Society Reviews on 7 May 2017, and highlighted on the inside front cover of the themed issue of Chemical Society Reviews to celebrate Pedersen’s achievements and the fifty years of supramolecular chemistry.