Hans Vonk
Robertson's relationship with the St. Louis Symphony Orchestra (SLSO) began in January 1999 when he made his first conducting appearance with the orchestra. Robertson's second appearance with the SLSO occurred in February 2002 at Carnegie Hall after the SLSO's then-music director Hans Vonk withdrew a few days before the concert due to health problems. Robertson agreed to substitute, and he and the orchestra had only one rehearsal before the concert. He later appeared with the SLSO in March 2003. The SLSO named Robertson its next Music Director in December 2003, effective with the 2005-2006 season.