Many people misunderstand the purpose of an NDA. When somebody asks you to sign an NDA to protect their idea, they don’t understand what they are asking. In such cases, you are absolutely correct, you should run. But NDAs serve a valuable function when a person or company already has intellectual property to protect. For example, a company has an existing software product, and needs to reveal some of their source code in to move forward with a business discussion with a potential partner or contractor. In such a case, an NDA is absolutely appropriate.