This is the complete fourth season of The Office: An American Workplace, coded to Region 1 (North America), so you will need a region-free dvd player. The UK version doesn't come out until 29 March and costs £22.99 to pre-order at Play or £22.49 at Amazon. £13.50 is the best price I've seen for this.
FYI, you can sometimes find a code online that will make your player region-free (as I did). Worth a Google if you're uncertain if your player can do region-free.