When I set out to learn about my mother's bridge club, the Jewish octogenarians behind the matching outfits and accessories, I never expected to fall in love with them. This is the story of the ladies, their game, their gen, and the ragged path that led me back to my mother.
1) Thou shalt not censor. Both partners need to feel completely free to float ideas no matter how idiotic.
2) Thou shalt control thine ego. No crying, whining, bullying or icing. No temper tantrums, passive aggressive maneuvers, or diva moves. No pouting, sulking, or “innocent” jabs.
3) Thou shalt be on the same page. More difficult than you think. Both writers must share a basic, core belief that they share a vision and equal ownership of the project.
4) Thou shalt watch thine partner’s back. i.e. control those sadistic impulses. Yes, you.
5) Thou shalt share a work ethic. How do you define a work day? Four hours? Eight hours? Eighteen? How many naps?
6) Thou shalt not be a credit monger. The first writer to yell, “That was my idea,” gets a time out.
7) Thou shalt have fun. And by this I don’t mean smoke tons of weed unless you’re Judd Apatow and Seth Rogan.
8) Thou shalt not sleep with your writing partner. (Unless you’re Judd Apatow and Seth Rogan.)
9) Thou shalt snack. The host writing partner should supply an assortment of junk food and apples.
10) Thou shalt know when to move on. That would be before one writing partner is found in pool of blood and the other is getting finger-printed.
(Am I missing any?)
Betsy Lerner 
Thou salt not work with a writing partner.
But take that with a piece of shalt.
Thou shalt read these ten commandments out loud to thy writing group or partners and strike down any who argue.
Thou shalt post these commandments on bulletin boards in Creative Writing Departments.
Thou shalt have a second snack accompanied by a drink.
Thou shalt persevere in the face of all these impossibilities.
Thou shalt feel free to build on one another’s ideas so that in the end, neither one of you remembers whose idea was whose because they’ve gotten braided so tightly together.
Thou shalt laugh a lot while working.
Thou shalt feel free to take the piece in a direction neither of you anticipated, then add a note saying, “It felt better this way, and I have no idea what happens next, but I know you’ll be able to make this shine.” And thy partner shall feel free to tell thee that thou art an idiot, then say, “But you know, this DOES work better…” and pull both thy behinds out of the fire.
Thou shalt not ignore your talents–mix, but don’t match. Anything good is alway more than the sum of its parts.
Thou shalt be a saint lest this shan’t apply to thou.
I confess that I may have broken the spirit of number 10. I’ve not been fingerprinted – yet – but I do need a new partner. Anyone?
Thou shalt actually contribute.
Good list. Would probably work any time you had to work with someone, not just with writing. Thanks for sharing.
Thou shat wring thy hands and shake thy fists at the heavens at the divine injustice therein; that the number ‘8,’ when typed onto a blog post followed by an open parenthesis, yields a smiley-face emoticom once it’s posted. My God, why has thou forsaken us?