This proposal requests partial support of Gordon Conference meeting expenses from the Computational Biology Program. Fundamental experimental, theoretical, and computational underpinnings of macromolecular crystallography have experienced explosive growth in recent years. In contrast to past Gordon Conferences, these computational and experimental underpinnings will be emphasized by bringing together major exponents of experimental and ab initio phasing approaches. Sessions will also be devoted to issues involving new experimental facilities, particularly the Advanced Photon Source.