Conductor Hans Graf, in addition to holding several major positions as music director, has made an exceptionally wide range of appearances as a guest conductor. He is also active as an educator. In 1984, Graf was appointed music director of the Mozarteum Orchestra in Salzburg, recording the complete symphonies of Mozart with that group. He was music director of the Houston Symphony from 2001 to 2013 and has continued to appear there as conductor laureate, earning a Grammy Award in 2018 for the orchestra's recording of Berg's opera Wozzeck. After several guest appearances with the group, Graf became chief conductor of the Singapore Symphony in 2019. Graf led the Russian National Orchestra, backing trumpeter Paul Merkelo on an album of trumpet concertos by Shostakovich, Mieczyslaw Weinberg, and Alexander Artunian in 2022. By that time, his recording catalog comprised more than 30 items.