The crystal structure of (π-C5H5)W(CO)3AuPPh3 has been determined. It consists of discrete molecules of the formula given, which are arranged in layers having tungsten atoms and their ligands near the centre and gold atoms on either side. The outer regions of the layers consist of phenyl rings. The packing of these rings leaves small unoccupied regions throughout the structure. The gold–tungsten bond length (2·698 Å) is slightly shorter than expected and the tungsten–gold–phosphorus angle (173·8°) is significantly different from 180°. The tungsten atom, formally heptaco-ordinate, may be described as at the central position of a distorted square pyramid, with the cyclopentadienyl ring at the apex. Bond lengths and angles are compared with those in related structures.