We've mentioned operating agreements in a few blogs, and we thought we'd go over it in more detail in this entry. What is an operating agreement and why does my LLC need one? An operating agreement is a key document for an LLC with a sound legal foundation. An agreement that is acceptable to all managing members of the LLC, even if you are a sole member of the LLC, will help your business run as it was intended. Well written operating agreements should give the LLC members peace of mind. We'll map out the basics of a good operating agreement below.