During this period, he also held a variety of positions at the Boston Symphony Orchestra's summer home in Tanglewood, serving as director of new music activities from 1965 to 1969 and as artistic director of the Tanglewood Music Center from 1970 to 1984 and creating the Tanglewood Festival of Contemporary Music.
Under denna period uppehöll han också en rad olika befattningar vid Boston Symphony Orchestras sommarhem i Tanglewood, fungerade som chef för nya musikaktiviteter 1965-1969 och som konstnärlig ledare för Tanglewood Music Center 1970-1984 då han genomförde Tanglewood Festival of Contemporary Music.