In 1971 the Libyan Department of Antiquities invited the Society to conduct a trial excavation at Ajdabiyah, with a view to defining the extent of the medieval Islamic occupation and determining whether the site would repay further investigation. The prognosis was good. Documentary evidence indicated that Ajdabiyah was already a caravan town in the ninth century A.D., that it flourished under the Fatimids and that it was destroyed or severely damaged when the Bani Sulaim and the Bani Hilal invaded the Maghrib in 1051. Furthermore, earlier excavations had revealed two medieval monuments, a ruined qasr and a mosque, both apparently Fatimid. As expected, the trial excavation, which was described in the Society's Annual Report for 1971, yielded positive results and in April 1972 we began a second, larger campaign. During the season we resumed excavations at the mosque and planned in detail the remains of the qasr. The Director-General of Antiquities, Mr Sadawiya, and the Controller of Antiquities in W. Cyrenaica, Mr. Abdussaid, did everything in their power to make the expedition a success and our Inspector, Mr Warfelli, gave valuable on-the-spot assistance. The Society sent a team of nine—Hilde Ainger, Sarah Jennings, Ruth Whitehouse, George Ainger, Warwick Ball, Peter Donaldson, David Jeffery, John Morrish and myself—and the Department of Antiquities provided accommodation and labour. The Trustees of the British Museum kindly released Mr Nicholas Lowick, who joined us to study the coins and epigraphy, see p. 4. The Department of Civil Engineering, Imperial College of Science and Technology, generously lent us surveying instruments. The project, therefore, was a combined operation and I wish to thank most warmly all those concerned.