Yes - My DH's ex boss (also family friend, not just a random ex boss) is always taking me out, we often go out as group and he'll send the rest home and we go for a drink afterwards. He's stayed round the house on more than one occasion when DH has been away with work. My Mum finds it most odd and I'm sure she thinks he's my bit on the side. He most certainly isn't though!

DH and I do this too- regularly. My closest friends (pre and post DH) are men, and his closest friends include some women, so it is natural for us that from time to time I go out for dinner with a male friend and DH goes out for dinner with his female friends. We also go out together with those friends, but we both recognise that the conversation changes and that it is not the same thing.
Like you, Pippi, I have had the impression that this was less than usual and certainly a couple of people have expressed surprise at the fact that DH is perfectly happy for me to go out for dinner with an ex boyfriend when he is in town. Like other posters have said, relationships are based on trust. We trust each other.

I do have one straight male friend whom I see for dinner every few months. I think it helps that we have met each other's partners a few times. But we are old school friends, and enjoy gossiping about old times, which deathly boring for our other halves, who have no wish to tag along.

DH is more of a man's man, so the issue of him seeing female friends one to one has yet to arise.

Yes I do, I have quite a few male friends and couldn't imagine not seeing them just because I was with a bloke.

What do people do, ditch male friends when they get a man or not have close male friends in the first place I wonder?

Our relationship wouldn't have lasted if DH had made me choose between my friends or them and I'm sure if asked he'd say the same.

I have done in the past (going for Chinese meal with a male friend as my then-boyfriend didn't like Chinese food) and also, the other way around, gone to a gig with my XP when he had recently married someone else, because both of us were huge fans of the band and his DW wasn't bothered.
If you are in a monogamous relationship, your partner is either trustworth or s/he isn't, end of. And it's not necessary to go out to dinner with someone to have illicit sex with them, you can do that just as well in the stationery cupboard during office hours.

I don't really have newly-acquired friends, male or female, who I'd go out in the evening with; that's more of a catching-up-with-longstanding-friends thing for me. And generally my newly-acquired friends come as part of a couple/family (tend to have met them through the DCs).

Yes. As it happens the only male friend I've done that with is gay, but that's because most of my friends, male or female, are now married or partnered with children and we tend to all get together as family groups or at the very least as couples. And I prefer that, too, to be honest -- I like forging new relationships and our children getting to know each other (same thing goes for the gay male friend, but his partner is insanely busy at work and so trying to get all of us together is a huge undertaking).

DH took a female friend to the rugby (and, I suppose, technically for dinner, if you count a roll from the hog roast ) a couple of weeks ago (it was an evening kickoff, so too late for the DCs and that meant I couldn't go either), and I wasn't bothered about that (I suppose, if I'm completely honest and navel-gazing, I might have been more bothered if I hadn't at least met her beforehand).

I go and stay with one of our male friends by myself and everyone is fine with that.

My OH goes out with his female friends and has been down to visit them by himself but we've all known each other for years and OH and I have been together for ever.

Sometimes I think it depends on how secure you feel, I know if I feel a bit crappy then I'm more jealous of it but it's more the going out unencumbered than who he's with iyswim.

this reminds me of When Harry Met Sally classic quote ' men and women cant be friends'

in my case tis true