Former Wales international Jonathan Thomas is to leave his job as Bristol forwards coach and rejoin Worcester for the 2020-21 season, to be replaced at Ashton Gate by John Muldoon.
Thomas will take over at Sixways from Rory Duncan, who will depart by mutual agreement at the end of this season.
"JT shares the passion we all have for Warriors to become successful," said director of rugby Alan Solomons.
"The decision to leave Bristol has been incredibly difficult," added Thomas.
"Since finishing playing for Worcester in 2015, I've continued to live with my wife and three children in South Worcestershire. We have fallen in love with the area and, as a family, are really settled.
"Obviously, I'm a former Warrior with a close affinity and passion for the club and its supporters. When Alan and the new owners spoke to me about the opportunity and explained the exciting vision they have, it was something that I felt was right for me personally and professionally."
Bristol director of rugby Pat Lam described Thomas as an "excellent team man and an outstanding young coach" whose contribution at Bristol over the last four seasons was valued by everyone at the club.
Three-times capped former Ireland forward Muldoon, 36, is currently Bristol's defence coach, having first joined the club in the summer of 2018 and helped them to their highest Premiership finish in 12 years.
"Working with Pat and the management team has been a fantastic experience," he said. "It's a truly unique culture that we have at the Bears and an environment that demands high performance, whether you're a player, coach or member of staff.
"We have a young, hungry set of forwards and some genuinely world class players, so everything is in place for us to continue to show progress next season and beyond."
The Bears are currently top of the Premiership, five points ahead of seventh-placed Worcester.