h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

In the US, the first time most people have to live with someone not their family is when they go to university; roommating is the norm. Some things I've found to help with this crazy form of living (especially if it's the first time one has lived away from parents and with someone else in their "space" for any amount of time):

Establish cleanliness rules right at the outset. A lot of people have different versions of what "clean" means, some don't have the word in their vocabulary. My roommate of two years and I are polar opposites in the cleaning area: I like things relatively neat, while she doesn't mind/notice clutter/dirty clothes/decaying food (I'm not kidding). It's impossible to totally change someone, but I asked her early on that, if I didn't bug her about clutter so long as it wasn't horrible, she at least maintain a pathway to the door and keep her dirty clothes out of my sight. Which she did. In two years, we've rubbed off on each other, though. Now she's almost neat and I'm turning into a slob!

"Mine is mine, and yours is mine" - No matter what the relationship between the two people is, I think setting boundaries of what one can and cannot do with another's stuff is somewhat important. In my freshman year of uni, I was the one with the computer and working stereo, and she was the one with the fridge - so we shared those things. Books/food/toiletries (girls do that sort of thing)/CDs/movies/etc were shared only after asking if it was allowed. No clothes sharing, but that's only cause we were at totally different ends of the size totem pole.

Personal space. This is harder to do in a dorm setting because of space limitations - ie, there isn't any space. We worked out a system of her having quiet time while I was at work or at class or at a rehearsal, and I would have me-time when she was at class or out partying. If we were both in the room, we were lucky enough to be able to at least sort of partition the room so that I could have my little enclave under her loft (where my computer was) and she could be on her bed (above me) - out of sight, out of mind. Luckily, we became good friends and thus did more seeking out of each other's company rather than trying to get away from it.

Sleep. My roommate and I operate on vastly different sleep schedules (that is, I sleep, she doesn't). We have yet to fix this to perfection, but we just decided on a concensus bedtime - no later than 1 in the morning if we have an early class the next day. She often wants/needs to stay up later, so she will go out of the room and into a lounge or the computer lab to finish her work if she needs to. The same happens if I need to go to bed earlier.

Bathroom rights. There is one single bathroom for every 4-person suite in our dorms, so a bit of fenangling sometimes has to go on. Normally we compare schedules and see if there are any massive problems (say, three people have an 8am class and need to shower before leaving), and then fix them accordingly. We were lucky enough to be able to partition the bathroom off into sections (sinks, shower, toilet) so multiple people could be in there at once.

Friends. Random visits are fine, overnight visits must be cleared with roommate first, *especially* in the case of significant others.

Food. We would switch off buying milk/soap/bread/juice. Or if we went shopping at the same time, we'd split the cost. The alternative is to only use that which you paid for.

I know that's probably not what you're looking for... but cohabiting and housemates aren't the only times when people may end up having to live together.

Sounds familier to me. I have gone through all this except my university is in India. But habits of room mates are universal it seems

Seems it. Though I think I've had an odd experience as Melissa (my roommate) and I ended up being great friends by the end of the second week we were living together. So we related almost off the bat in terms of rules and just dealing with each other (I'd much rather live with a friend rather than someone who simply shares your room). I know of people who do nothing but fight with their roommates; there was even news of one roommate who kicked the other out permenantly one time in my freshman year.

Personally, I feel sorry for people who don't have roommates while at university. While it can feel like an encroachment on your adulthood and privacy, I've found that roommates more oft than not become invaluable friends, especially if you're far away from home.

It also seems that what appear to be insurmountable differences at first often make one or both roommates much more well-rounded people. One dorm manager from my college days pretty much insisted on pairing opposites as much as possible, lived through drama for a week, and then had a pleasant rest-of-year as they both grew up a bit.