As I understand it, the writer who is creating a fictional novel must have the entire manuscript complete before he begins to approach either a literary agent or a publisher. I thought the same was true for a non-fiction work. As I wrote my last two books, I had dreams of finding a literary agent, but after the books were complete, I knew it could take forever to find one. It was more likely than not that I wouldn't find one. So I have chosen to seek out a literary agent for my next book. With that being said, the process is somewhat different when dealing with fiction vs. non-fiction works. For non-fiction works, the author can seek out a literary agent or a publisher without ever having started his or her manuscript. With that being said, the agent or publisher, if they're even interested, will likely ask for a few sample chapters. So the dilemma becomes whether to write the chapters first, or do the book proposal first. In my case, I'll likely work a little bit on both with the hope of having a few chapters complete when the book proposal is complete. In addition, I'll have to include a query letter. The query letter is the one shot at selling the idea to the agent or publisher, so it has to be the best. It all seems a little intimidating to me, but I've decided to go through with it this time. I recently read that J. K. Rowling's book had been rejected several times until a publisher's daughter demanded to read it. I'll stay steadfast in my determination. I promise not to get discouraged by rejection letters. You all will be the first to know when I find my agent.