Depends what kind of business are you talking about?
I do internet marketing It took me some time to figure out how to get leads. I am still working on it.
I have had quite a few business partners #1 you have to put them threw some tests you dont want to get stuck with a lazy person where you are doing all the work.
#2 Get a contract put into place that says if the other person doesent meet monthly expectations the partnership is over and it is split a certin way Dont wait until money rolls in and you are screwed because they are acting like a Jackass. Before you start any partnership have an out strategy
#3 Montly X amount of dollars must be spent on advertising I dont know what money does to people but as soon as it comes in they start raking it into there pocket and froget about the company it is very frustrating having a partner that doesent belive in marketing.
#4 Know your values and pick a partner that shares your values and beliefs it will go a long way down the road