International conferences on phenomena in ionized gases have traditionally been held once every two years since 1953, when the first such conference was organized in Oxford by Dr. A. von Engel. The tenth (celebratory) conference was again held in Oxford and was attended by some 750 participants from a large number of countries. By comparison with previous conferences, in Bucharest (1965) and Vienna (1967) for example, there were thus fewer participants, for the attendance at Bucharest and Vienna had been 750 and 1000, respectively. The subject matter of the conference has remained largely unchanged since 1965 (the Belgrade conference), but there is a trend towards limiting the topics. The organizing committee of the tenth conference, for example, did not accept papers relating to thermonuclear fusion, MHD generators or mathematical modelling, but the remaining rather broad topics were not divided up in accordance with any discernible general principles.