Williamson, 68, joined the Panthers in 1995, the year they started play. He stayed on through the entire tenures of Capers and George Seifert and was with the Panthers since John Fox arrived in 2002. He even did a stint as offensive coordinator under Seifert, but Williamson was best known as one of the top wide receiver coaches in the NFL.
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"Richard was a valuable member of our coaching staff," Fox said. "He helped Muhsin Muhammad and Steve Smith develop into Pro Bowl receivers and was someone we all leaned on because of his experience and knowledge."
Williamson had been asked about the possibility of retirement for years, but previously had said he wanted to keep coaching.
"I have enjoyed being with the Panthers since the beginning," Williamson said in a statement released by the team. "It was great to be part of the development of the Panthers from an expansion team to a Super Bowl contender, and I appreciate the way [owner Jerry Richardson] does things. This organization is the class of the NFL and I have tremendous respect for him."
Muhammad, Smith, Patrick Jeffers, Raghib Ismail and Mark Carrier each had at least one 1,000-yard receiving season under Williamson.
Williamson was a head coach in Tampa Bay for three games in 1990 and the entire 1991 season. He went to Cincinnati for three seasons before joining the Panthers. Williamson began his NFL coaching career in 1983 with Kansas City.
Williamson also was a prominent college player at Alabama. He played wide receiver when Joe Namath was quarterback and Bear Bryant was coach.
Sources: Carolina Panthers grant coach John Fox chance to opt out of 2010Guti ready for Real return
