Ireland A prop Mike Ross has extended his contract with Harlequins until 2010.
Ross has been a regular for Quins since signing from Cork in 2006 and was part of the Ireland A squad that competed in the 2007 Churchill Cup.
Highly-rated loose-forward Tom Guest and winger Ugo Monye also signed similar length deals.
Director of rugby Dean Richards said: “I am delighted that so many of the players have re-signed for Harlequins, showing the belief they have in the club and each other.
“We are building a strong squad for the future and it is great to see so many homegrown players coming through.
“I am looking forward to seeing all these players performing strongly next season.”