Real data offers an opportunity to test our imaging techniques further. Common-azimuth migration is an attractive method for seismic imaging in complex media and remains a subject for further research. Its computational cost, illustrated in this particular example, can make it an attractive alternative to widespread Kirchhoff methods. The imaging of the North Sea data reveals lithologic structures focused with high resolution. Angle-domain common-image gathers highlight imaging insufficiences around the steepest parts of salt flanks. They also offer opportunities for residual migration and velocity estimation. An extended migration scheme, which incorporates a wider range of data in the cross-line direction to account for lateral velocity variations, is being examined Vaillant and Biondi (1999).