Closely held businesses are frequently co-owned by friends and relatives, and are governed in a friendly, informal style. This can work well until it doesn't. Changes in ownership or control through divorce, inheritance and other circumstances, economic hard times or other events, frequently trigger disputes among the owners and, all to often these disputes culminate in lawsuits that can threaten the very existence of the company. This article is a succinct basic primer for closely held Michigan corporations and LLCs on avoiding and defending shareholder and member oppression lawsuits.