I think its hypericum - it seeds itself quite readily round my garden.

Definitely hypericum (St Johns wort). Watch it 'cos you'll have little 'uns all over the place!!

Harvester, do you know any Flower Arrangers? I'm sure they would be only too willing to have some of the stems cut to use in flower arrangements - especially if this shrub is needing to be cut into shape!

There are lots of hypericums. I think this one is androsaemum, common name tutsan. The berries are just as pretty as the flowers aren't they?

Hello Harvester! There are so many hypericums these days ... This particular one behaves a little like a fuscia and looks pretty dead until late spring. It is worth keeping for its later summer colour and autumn foliage and berries. I have not found it to be a particular pest (just lucky maybe?!). Cut it down in late spring when you see new shoots appearing at the base - just like a fuscia!

Thanks to everyone who answered my question. :)