Anyone can write a separation agreement. However, writing a separation agreement can require a high level of skill and understanding of family and contract law. If an agreement does not accurately reflect the wishes of each party, then the document may have future legal consequences. If a person chooses to write a separation agreement, at the very least, the parties should have a lawyer review it. A separation agreement at first glance may seem very straight-forward; however, it can quickly lead to complex problems.