As part of the man formerly known as JimBobOz's manifesto, I'm going to attempt posting a new thread a week.  

Even though RPGs are a social group event, I've never been able to fully embrace "The Party" concept.  I understand the ease for the GM and the ability for player specialization but I tend to get tired of the metagame forced togetherness.  Much of the time I spend examining my roleplay experiences leads me to thoughts of breaking down, if only the illusion of, The Party.  It's the crux of roleplaying for me, playing with friends or exploring a character.  It comes from a player's perspective, of course.  I've only been able to come up with solutions based on two methods:  

1.  Make The Party work outside of the characters.
2.  Make individual characters The Party through a shared campaign narrative.  

#1 relies on The Party being the character where the group is playing its members.  The premise of the campaign is based of the party.  As an example I would use Saving Private Ryan where the members are often in flux.  Their individual efforts are secondary to the success of the group.  Only the group experience is explored throughout the campaign.

#2 relies on individual character exploits sharing an effect on the campaign premise that affects all of the other characters actions.  It would seem a semi-episodic form of play concentrating on the impacts of the individual.  Think of a novel concentrating on three individual storylines interweave to form a campaign plot.  

I may be the only one that's bugged by this,but are there other mechanics for encouraging this kind of play in a campaign with friends?

Well, there are a few games where character relationships are supported by game mechanics, such as Active Exploit's "threads". And in many games the GM will give you XP for succeeding in some mission.

Is that the sort of thing you're talking about?

Well in my Sci-Fi game set in the 57th century its VERY easy to have the concept of an "adventuring party".
 
The Party is the crew of a small-ish Merchant freighter. When in the vacuum of Space , you BETTER work together or your ass gets sucked out into the void.

 The ship may have a commander - but she encourages voting on major decisions by the crew pretty often. She also wants the other players (And the NPCs ) to argue their case when they want to go off in a particular direction or decide on a new job or goal for the group.

  It works out well  - the player who runs that character has done a LOT of decision making in her real life and used to run a business or two.

- Ed C.

Parties make perfect sense!

Harry Potter: "We're dormmates! We'll cover each others' asses sneaking around authority figures and in doing so get caught up in each others' plotlines. Or just Harry's."
Naruto: Same, except replace "cover each others' asses" with "at each others' throats" and "Or just Harry's" with "Naruto, you SUCK!"
Samurai Champloo: Okay, this one makes no sense, and so serves as a poor example. But a party where the members hate each others' guts is good RP fodder.
Cowboy Bebop:"Your ship is big enough to live in? You have a garage in this thing? Awesome! And here I thought I was going to have to live in my car."
Fullmetal Alchemist:"We're brothers. He has no body, and I wanna fix that. Also, we kinda turned our mom into a pus-spewing sin against nature. Been meaning to fix that too, heh-heh."
Ghost in the Shell:"This is my job. I do it without changing my facial expression. Ever. This is my partner. Same goes for him. And there's this human guy who occasionally stares vacantly and has a bad mullet. Worse than mine. He's there 'cause he can't get hacked."
Narnia:"WTF... there's a portal to an alternate reality. In my sock drawer! Let's stick together. It would suck to get lost, like so many stray socks."

For an alternative, consider just making the players each head of one division in a single organization. Let them stat out a couple characters, and pick one to send out on a given mission. Always a party. Never the same. Lots of characters and some amount of room to put them at odds.