When composing chapters for a book, try to contain scenes within chapters, similar to scenes in plays. As long as the scenes are related to a single block of action or topic, keep them within the same chapter. If a change or transformation is involved, by all means, start a new chapter. Another way to determine when to start a new chapter is to try to draw the plot for each chapter. You should have a beginning, middle, and end. Your beginning is what incites the action in the chapter; your middle is the most exciting part of the chapter, the height of the action; your end is a drop in the excitement or the ending of the action. If you have more than one beginning-middle-end, consider breaking those into separate chapters. Certainly, two beginnings deserve separate chapters or at least separate sections, if you are writing something with a broad time-scape and your chapters cover different years or eras, as historical novels are wont to do. Many contemporary novels make use of cinematic chapters, cutting off chapters just at the point the action reaches a high point. This is very effective for thrillers because readers are kept in suspense and are riveted to your story, wanting to find out what happens in the next chapter. However, do give your readers relief and let them settle a bit in the next chapter as you prepare them for another more exciting or more intriguing event. Change the pace in chapters so your readers don’t get tired either from very slow chapters or from very quick-paced ones. Whatever you do, however, don’t always end a chapter with the end of the day and the characters going to sleep because that can become predictable, tiring, and boring. Your readers don’t need to see your characters going to sleep every night at the end of each chapter, especially if nothing happens when they sleep. It can easily become a signal to your reader to put your book down and go to sleep. Remember, variety is the key to keeping your readers involved and interested.