Most of my professional design experience is in non-fiction. Books on martial arts, violence dynamics, history, memoirs…they’re some of my favorites. With non-fiction books, frequently the client has images of their own that they’d like to use. It’s extremely important that the people in these images, if they’re other than the author, have signed model releases. It’s also important that if someone other than the author took the image that they want for the cover, that they have permission from the photographer to use the image. You may not need to get the photographer’s permission if the image was taken with the author’s camera or phone for the author’s own use. Copyright law is not super-complicated, but there are nuances that a lot of people don’t understand, so you can expect that I’ll ask some questions and give you what information I have about image use. I’m not a lawyer, though! If I have the slightest doubt I will usually suggest that either you consult a copyright lawyer, that you purchase a stock image (or I may purchase a stock image on your behalf), or you use an image that is free and clear of any copyright issues.