Link: 5 Things to Consider Before Saying "I Do" to a Business Partner

From Entrenpreneur.com

The gist here is that you need a lawyer. Maybe that's just my interpretation. 

1. Perform due diligence
2. Make sure you lawyer up
3. Ensure you have exit strategy
4. Protect yourself
5. Protect your brand

2. Make sure you lawyer up. If the legal fees in the beginning of a business relationship don’t make you wince, then you’re doing something wrong. When you partner with other people, every aspect of the business relationship should be put down in writing --  including the goals for the company, duties and responsibilities of the partners and an exit strategy. Every sentence of a contract -- no matter how innocuous -- should be looked at by a lawyer. Since tax laws can be tricky, have your accounts receivable/payable arrangements scrutinized by an accountant.