"I've never had occasion to use one magnificent tip from a well-known author, but I pass it on anyway: "Keep an eye on the trade press. When an editor moves on, immediately send your precious MS to his or her office, with a covering letter addressed to said departed editor. Say, in the tones of one engaged in a cooperative effort, something like this: 'Dear X, I was very pleased to receive your encouraging letter indicating your interest in my book, and I have made all the changes you asked for....' Of course they won't find the letter. Publishers can never find anything. But at least someone might panic enough to read the MS."