How do you protect yourself in a joint venture so the other company doesn''t sell the business in the future, leaving you on the outside?

If you are a joint venturer, it is hard to believe that anyone would buy a business without speaking to all of the owners. Even if the business was sold, if the proceeds were not shared according to ownership there would be a right to recover in a lawsuit under many legal theories such as breach of fiduciary duty, and probably fraud/concealment and conversion. A joint venture agreement in writing can have great benefit in addressing this and numerous other issues.