The atomic structure of a (331) [Sgrave] = 19/ tilt boundary prepared from an Au bicrystal has been investigated by very high resolution transmission electron microscopy. It has also been possible to confirm independently the type of contrast obtained in such a micrograph by dynamical diffraction and computer image simulations and correlate the image features to the atomic position data. Close agreement has been achieved between two relaxed boundary structure models and the computer-enhanced [Sgrave]=19 micrograph viewed along the tilt axis direction. Direct measurements of the interfacial dilatation of the (331) planes parallel to the interface and the relative translations of the two crystals on either side of the interface have also been made. © 1986 Taylor & Francis Group, LLC.