The X-ray crystal structures of five new crown ether complexes of Na ' and Ag ' are reported, namely: [Ag(18-crown-6)(H 2 O)(NO 3)] (4), [Ag(18-crown-6)(CF 3 SO 3)] (5), [Na(18-crown-6)(H 2 O) 2 ](CF 3 SO 3) ×/18-crown-6 (6), [Na(18-crown-6)(MeOH) 2 ](BPh 4) (7), [Na 2 (dibenzo-30-crown-10)(H 2 O)(MeOH)](BPh 4) 2 ×/MeOH (8). Compounds 4 and 7 exhibit intramolecular OH/Á Á Á/O crown hydrogen bonds resulting in marked distortions of the complex in order to simultaneously maximise ion Á/dipole interactions with the metal centre and satisfy the hydrogen bonding requirements of the system. Compound 6 exhibits intermolecular hydrogen bonding interactions to the uncomplexed crown ether, while compound 5 does not contain any hydrogen bonding protons but forms a surprising intermolecular pseudo -agostic CH 2 /Á Á Á/Ag interaction.