The first time it happened I was a young, drunk twentysomething swimming out of her depth with the soaks in the Colony.
"And you are ...?", the older, drunker, posher woman drawled, sprawled across the lap of someone related to the famous and talented.
"Louise." I answered.
"Louise who?" she hooted back, irritated.
"Brown" I mumbled, befuddled not just by the large gins I'd been necking for, ooh, about six hours that evening. Did she want to write a letter to me? Fill in a form? Write a cheque?
She shook her head with a disconnected smile and went on with her conversation without me, leaving me to stew in what I assumed was my own jus de social faux pas.
Was it a class thing, I wondered, would she think she might know my family, "Ah, the Dagenham Browns, aren't you related to Madge from the Tote?" Not likely.
Years later I read an article by someone like Alison Pearson where she opined on the habit of young women who only ever introduced themselves as "Samantha" or "Tara" wilfully omitting their last names.
Alison (can't have been Julie, surely?) decried this as the habit of the vain and the vacuous, reducing themselves to a page 3 cartoon caption "Keeley likes Jeffrey Archer novels and chipmunks, and doesn't agree with ecomonic monetary union". She may even have quoted a fine example of this type, the brilliant spokesmodel character SanDeE* played by Sarah Jessica Parker in L.A. Story.
I'd finally got it. The woman in the Colony (can't remember her name - first or last) thought I was being dumb and cute whereas I knew that there was absolutely no chance she would have heard of me and didn't even consider that it might be useful in future for her to know I was a Brown.
To this day I have friends (admittedly not all that close) of whose surnames I have no idea, any confusion with the similarly monikered clarified by their distinguishing features. For example, two of my mum's golfing chums will always be known to me as Big Doreen and Little Doreen and a beautiful, sweet friend of a friend known affectionately as Suzy Boobs.
But I was caught out again on Thursday night when a fellow media industry worker (who shall rename nameless, I bear no ill will) said,
"I didn't catch your name"
And I answered simply "Louise".
This time he was left to physically implore me with an upturned face and outstretched palm to finish the job.
"Oh - Brown, Louise Brown."
Again a shake of the head and a move swiftly on - transporting me right back to that smoky room of my youth.
So really all this post, nestled alongside my various media-related mental meanderings, is, is an elaborate note to self: you are 35 - not 5 - and in social situations it is useful to hear your full name for any number of reasons - professional and personal.
I suppose the likes of Facebook have changed this quite a lot for folks younger than I - you end up knowing people's surnames as well as their inside leg measurement with the click of a mouse - and, scuse me while I adjust my chip, I'm sure there is a little bit of socio-economic change in there somewhere; my Great Aunt Madge never had to network for starters.
Most significantly, in a world where we now know so many freaking people in so many shallow ways (206 Facebook friends, 200 personal email contacts, 121 LinkedIn connections etc. - and that's with no massive outreach effort), the need for a full, distinct name becomes all the more useful. I've even considered the Googlability of my future offsprings' names as a determining factor in their nomenclature given that I'm saddled with the top slots taken up by the first test tube baby.
To think people ask me why I haven't changed my last name since I've got married - I have enough trouble recalling the first one I was given, for heaven's sake.