Annual Spring Conference of the X-ray Analysis Group of Institute of Physics was held in London on 13-14 April, 1950. subject was The production and application of high intensity X-ray beams. In addition to the evening discourse delivered by Prof. A. Guinier of the Faculte des Sciences et Conservatoire National des Arts et Metiers, Paris, sixteen papers, together with a number of shorter contributions, were given during the four sessions; an exhibition of apparatus and photographs was also held. discourse, and other contributions, and the discussions are summarized in this report.