after his graduation koechlin became a freelance composer and teacher. he married suzanne pierrard in 1903. they had five children. their son yves later married paul langevin's granddaughter noémie. after 1921 he regularly corresponded with his former student, composer catherine murphy urner in california. in 1909 he began regular work as a critic for the "chronique des arts" and in 1910 was one of the founders, with ravel, of the société musicale indépendante, with whose activities he was intensely associated. from its inception in the early 1930s to his death he was a passionate supporter of the international society for contemporary music, eventually becoming president of its french section. from 1937 he was elected president of the fédération musicale populaire. at first comfortably off, he divided his time between paris and country homes in villers-sur-mer and the côte d'azur, but after the onset of world war i his circumstances were progressively reduced, he was forced to sell one of his houses and, from 1915, took work lecturing and teaching. partly due to his vigorous championing of younger composers and new styles, he was never successful in his attempts to gain a permanent teaching position for himself, though he was an examiner for many institutions (e.g. the conservatoires of brussels, rheims and marseilles). he was rejected for the post of professor of counterpoint and fugue at the paris conservatoire in 1926 by 20 votes to two (the two being albert roussel and maurice emmanuel), but from 1935 to 1939 he was allowed to teach fugue and modal polyphony at the schola cantorum.