From 1957 to 1969 Gilbert was director of wind studies at the RMCM, before moving to Stetson University in Florida in the US, where he remained for ten years, as director of instrumental studies and conductor in residence. He was in demand for masterclasses in the US and Europe. Gilbert described the keynote of his teaching as "compassion", but, an obituarist commented, "inevitably it was also his meticulous attitude. and his ability to concentrate furiously that made an indelible impression on his best pupils." His life and influence are documented by Angeleita Stevens Floyd in "The Gilbert Legacy", published in 1990, and reissued in 2004.