The first thing you should write before entering into a co-authoring relationship is a collaboration agreement, said Stephen Gillen, an attorney with Wood, Herron & Evans, L.L.P.

“Do it before you write the manuscript, before you sign the publisher’s contract, before you write the sample chapters, before you write the outline, and before you write the proposal,” he said. “Do it first. If it’s too late to do it first, do it NOW! If you think you don’t need one, you’re wrong. By the time you realize you do, it’s probably too late.”