The experienced Welsh scrum half joined Gloucester on loan in 2009 after a short spell with Championship club Moseley and will now move to Warriors for the start of next season. It was during this period that Williams took a degree in Sports Management which is now completed.
Having agreed a one-year deal with Worcester Warriors, Williams will be moving to Sixways Stadium this summer.
Williams commented on his move and said: "I'm really excited to be playing for the Warriors next season. I'm so hungry for rugby and I can't wait to start playing again."
"Looking at the Championship I can't see why Warriors can't finish top and then go back into the Premiership the following season. The Championship requires a great attitude, every game is going to be like a Cup Final and Warriors need to be at the top of their game every week. I think that is something the Warriors can do and I'm looking forward to the challenge."
"I'm also pleased to be playing under Richard Hill. During my time playing for Bath I experienced the huge legacy that he has there, so to be able to work and learn from him being a scrum half would be tremendous"
New Head Coach Richard Hill spoke highly of his new signing and said: "Andy brings with him great experience and enthusiasm which I feel will be a great asset to Worcester Warriors."
"Andy has played at the top level with Bath, Gloucester and Newport Gwent Dragons and is spoken very highly of at all clubs. We are extremely focused on giving as much opportunity to the young scrum half's as possible at Worcester and I feel that Andy will compliment that."
"At both Bath and Gloucester Andy was highly motivated and was always willing to give help to the younger players. He has a huge amount of experience and can make key decisions especially when it comes to the bigger matches in the Championship and this will no doubt rub off on the others."
"He brings both experience and knowledge from playing in the Premiership and the Championship with Moseley, so he is already familiar with the other clubs and the way that the league is played which is very important."