 After the height of Elmo's popularity, especially the "Tickle Me Elmo" craze in 1996, Clash's responsibilities at Sesame Street increased. He recruited, auditioned, and trained its puppeteers, and became the senior Muppet coordinator, a writer, director, and co-producer of the "Elmo's World" segment of the show. Clash worked with and mentored the puppeteers of Sesame Street's international co-productions. He found working with the co-productions "a lot of fun" and "very rewarding". He worked on the 1985 feature film Follow That Bird. In 2007, he was promoted to senior creative adviser for the Sesame Workshop. Until 2011, he was the sole performer as Elmo in all his public relations appearances, making his schedule, as he called it, "crazy". Cheryl Henson, president of the Jim Henson Foundation, called him "essential" to the show.
