Eoghan Hickey will leave Munster at the end of the season and take up a two year contract with London Irish.
The 25 year old joined Munster on a one year contract from Leinster and has represented Ireland at schoolboy, under-21 and A levels, including last year's Churchill Cup tournament.
Hickey said: "My move to England involves a lifestyle change and the challenge of playing in the Guinness Premiership. From what I've seen that demands a continuity of top class performance week in, week out and it will be good to be involved.
"London Irish plays the style of rugby that I enjoy; I'm looking forward to doing so in front of the club's exceptional supporters."