The office party is a great opportunity for many single women and men to finally get their claws into attractive colleagues.
But when it comes to flirting, many singletons just don't know where to start.
The secret, says flirting expert Jean Smith, is to remember that flirting is all about the person you're doing it with, and not yourself.
Social anthropologist Smith, who runs 'Flirtology' seminars and Flirting and Walking Tours of London, says: "The bottom line of flirting is making people feel good about themselves, so you have to put the focus less on yourself and more on the other person.
"When people show interest in you, you're obviously going to like them - everyone's favourite subject is themselves."
Smith, who has researched people's flirting habits in six cities in Europe and the USA, has taken an innovative approach to solving Britain's flirting problems with her Flirting and Walking Tours of London.
Described as "the ultimate icebreaker", the tour is a mix of anthropological research and fun tips for relaxed flirting as Smith takes wannabe flirters on a walk round the capital's flirting hotspots, including a supermarket, the National Portrait Gallery and Covent Garden market.
Smith explains "methods of attack", or ways to approach people, including smiling and using eye contact, and then gives the group tasks like striking up a conversation with a stranger in the supermarket.
From her research and experience with the tour, Smith has found people approach flirting in different ways depending on how they define it.
The dictionary definition of flirting is "to make playfully romantic or sexual overtures", but when Smith asked 250 people what they thought it was, there was a marked gender difference in the answers.
"Men seemed to think that flirting had more sexual innuendo than women," she says.
"Whereas women thought of it more as being friendly and communicating."
She adds: "Good flirts are aware of the other person - they'll be aware of their reaction to things they say."
So far the tours have proved to be a success, with some participants finding true love thanks to Smith's tips.
"Someone who came on my tour was in her local supermarket the next night practising the things she'd learned," she says.
"A guy followed her out of the shop after she'd been smiling and making eye contact with him in the queue, and asked her if she'd like to go out for a drink with him and his friends.
"Now they're married and expecting their first child.
"If she hadn't been on the tour she might have thought he was cute, but not done anything about it.
"I'm not sure if he knows that she was using her new-found flirting techniques on him even now. But they can obviously change your life forever."
Smith believes it's the fear of rejection that stops many people from flirting, and stresses: "Rejection isn't such a big deal - you won't be swallowed by the earth.
"If you look on flirting as just having a chat, with no hidden agenda, you won't have as much to lose if nothing comes of it. My biggest tip for everyone is to just do it."
All the parties at this time of year are, of course, a great opportunity for flirting - in fact, anthropologists call it 'cultural remission' - where there's a temporary relaxation of normal social restrictions.
In layman's terms, you could call it letting your hair down.
Smith says: "The month of December and Christmas parties seem to be a sort of 'Get out of jail free' card, where people allow themselves to just go for it."
However, she suggests a flirting measure that many will find virtually impossible at a Christmas party: Don't drink too much.
While a lot of us may believe we need some Dutch courage to have enough confidence to flirt, Smith says if you want to flirt with someone you already like, being sloshed could ruin your chances of romance.
"If two people are totally drunk, it might make it easier to flirt, but you might be flirting with the wrong person," she warns.
"If you like that person, they may not take you seriously the next day."
She says the English are often not brave enough to flirt because they're worried about coming on too strong - although that doesn't happen very often, unless alcohol is involved.
"There's nothing wrong with having a couple of drinks first, but if you think the more you drink, the easier it's going to be, you may go over the line and spoil things," she explains.
However, she does agree that if you've had a similar amount to drink as your 'target', it "makes things a lot easier".
"It's all about starting a conversation, and not being so self-conscious," she says.
If you're in a group at a Christmas party, check out how often the person you're interested in is looking specifically at you.
"Men are pretty straightforward - women need to stop expecting them to relate like they do," says Smith.
"If they're staying there talking to you, they like you."
She adds that men seem to think a woman's flirting with them if they flick their hair - although women usually deny this, saying it's something they do anyway.
But while it won't hurt to flick your hair if you see the man of your dreams at a Christmas party, the one thing you should never do is let him know you're desperate.
Smith warns: "Desperateness and neediness are the least attractive characteristics anyone can have.
"A guy will be able to sense if you're desperate, and you need to be really careful. It's an immediate turn-off."
She adds: "Successful flirting isn't about getting something from someone, it's about giving the other person confidence and making them feel good.
"Just think you're going to meet some really interesting people and you're going to have fun."
And for some, having fun is the whole point of flirting, says psychologist Dr Simon Moore, of London Metropolitan University.
"People can flirt outrageously without intending anything," he stresses.
"It has, for some, become a social game - one where the normal rules of social interaction are made more flexible.
"Just playing the flirting game for some is the aim, not the tool to produce any other outcome."
If there is a sexual motive for flirting, Moore says it's part of an evolutionary process to quickly judge the value of potential mates without too much effort.
He points out that most animals, right down to fruit flies, engage in plots and plans for attracting others, and adds: "We are no different. Flirting is a little like taking out mating insurance."
Dr Simon Moore's flirting tips:
:: Smiling is the most effective tool in a flirting toolbox - people like you more and think you're more attractive if you smile at them.
:: Raised eyebrows, eye contact that's more than just fleeting and a hair flick for women can all help.
:: Lean in towards the other person.
:: Take sideways glances - when you're attracted to someone, you can't help checking out their assets.
:: Laughing can endear you to the other person.
:: Try mirroring - people mirror each other's body language when they're attracted with similar gestures.
By Lisa Salmon