UNDER the above title, an interesting new form of collaboration between twenty-five of the major scientific societies and technical institutions of Great Britain has been effected: the Committee has now issued its first annual report, rendered to the councils of the collaborating institutions concerned. The principal objects of the Joint Committee are threefold: (1) to promote joint discussions on the wider aspects of the subjects of materials and their testing ; (2) to assist a co-operating institution or society in the presentation of a paper or group of papers dealing with a more detailed aspect of one of these subjects ; and (3) to undertake those duties with regard to international matters which properly devolve on the Joint Committee in accordance with its terms of reference. The main activity in the period reviewed by the report was the organization of a general discussion on "Notched Bar Testing" held in Manchester on October 29, 1937, in which this interesting subject was reviewed in relation to research and opinion at home and abroad. Four comprehensive papers were submitted and these papers, together with a record of the most informative discussion which resulted, are now available in pamphlet form, obtainable on application to the secretary of the Manchester Association of Engineers. The Committee is now organizing a second general discussion on various aspects of "Nondestructive Testing", which will centre around papers presented by selected experts in Germany, Holland, the United States and Great Britain, on the use of X-ray, gamma-ray, magnetic, electrical, aeronautical and other more general methods: this discussion will take place in London in October or November of the present year. The pooling of the efforts of technical bodies in promoting discussions in the wide and most important fields of the materials of construction should go a long way towards satisfying a long-felf want, and the further activities of the Joint Committee will be followed with much interest in scientific and technical centres.