Some Native American tribes believed that Crow was the keeper of the sacred law and could shape-shift. He was seen as an omen of transformation. Crow can move through space and time, they believed, and has the ability to move in the past, present and future at the same time. One source I read about "Crow medicine" said that when you meet Crow, he could be telling you that there will be changes in your life, and that you must be prepared to let go of your old thinking and embrace a new way of viewing yourself and the world. More on the blog.