Measurements of the wave field corresponding to regular, oblique waves produced by a segmented wave generator have been made. Contours of wave height and wave phase have been obtained for several wave periods and directions, both with and without the presence of a large cylinder in the wave basin. These are compared with the predictions of a computer model based on linear diffraction theory. The comparison is generally quite favourable, with the principal features of the wave height and phase plots being reproduced by the computer model. In contrast to the snake principle, the numerical method appears able to account adequately for the effects of wave diffraction and reflection.