Society for Contemporary Music (ISCM), at Brussels in 1950. In 1949, he attended seminars on music held at the Darmstädter Ferienkurse in Germany (including lectures by Leibowitz on twelve-tone technique, and talks by Messiaen and Fortner). Shortly after returning from Darmstadt, Lidholm wrote a brief piano work, Klavierstück 1949. It is not directly inspired by Arnold Schoenberg's similarly titled piano piece, but Lidholm was familiar with it. Fyra körer (“Four choruses”) from 1953 also uses a free application of twelve-tone technique. In late 1953, Lidholm pursued further compositional studies with Mátyás Seiber in London for several months. Work from this period includes the Invention for various instrumental combinations and Concertino, a 13-minute chamber work he wrote upon the commission of the Guildhall Music Society. During his time in London, Lidholm made contact with Messiaen and Luigi Dallapiccola. Within a year after his return to Sweden, Lidholm had completed a suite for cello and piano that pays tribute to Dallapiccola, and Lidholm produced his first large-scale orchestral work, Ritornell, in 1955, the piece with which he became internationally known. Lidholm remarked “After some years of mainly working with chamber music, I desired to test my abilities in a work for larger ensemble.” It made use of large cluster chords and protracted use of percussion. In the ensuing years, Lidholm's works were performed in different cities, especially within Sweden and Germany. Lidholm, in his prefatory remarks on his compositional style in Ritornell, quoted Igor Stravinsky's definition of music as “…a spirit’s free investigation.” He composed in a number of styles of the course of his career, but never keyed his music to a methodology within any one of those styles. Thus, there is not the systematization of Hindemith in his works from the forties, or a strict serial technique in his works of the fifties. Only a small percentage of Lidholm's serial music subscribes to strict pitch order throughout the work. In Ritornell, for example, extraneous pitches are freely integrated into row order, and there is no deliberate effort to maintain an atonal orientation. International recognition: 1956–1960 In 1956, Lidholm left his conducting post in Örebro to assume the head of the Chamber Music Department at Swedish Radio. He was instrumental in establishing the periodical Nutida musik (“Contemporary Music”) as an adjunct to the music series of the same name begun in 1957 by Swedish Radio. It was at this time that