Brighton have signed Joel Veltman from Ajax.
Albion triggered Veltman's release clause of just over £900,000.
The 28-year-old Netherlands international can operate at centre-back or right-back.
Veltman is Graham Potter's second signing of the summer following the arrival of Adam Lallana.
"We're delighted to welcome Joel to the club. He has terrific experience from his time with Ajax including the Champions League and, of course, with the Dutch national team," Brighton head coach Graham Potter said.
"He's an excellent defender who can play at right-back and at centre half, but he's also comfortable in possession.
"He is really looking forward to the challenge of playing in the Premier League and we're delighted he is now a Brighton player and we're looking forward to working with him."