Morocco's El Ahmadi joins Aston Villa
Midfielder El Ahmadi, 27, played a major role in Feyenoord's second-place finish in last season's Eredivisie, which earned the club a place in the Champions League.
"It was always a dream of mine to play in the Premier League," El Ahmadi said on Aston Villa's website.
"I think this is the best league in the world. It will be a challenge to show people what I can do."
El Ahmadi is new Aston Villa manager Paul Lambert's first signing as he looks to strengthen the squad that could only manage 16th in the Premier League last season.
"Karim will help the team, I have no doubt about that," Lambert said.
"He's a really good footballer and he's played well in a good team, a big team, and I'm looking forward to working with him."