1. Read the famous two early. The Murder of Roger Ackroyd and And Then There Were None are the two most likely to be spoiled for you by somebody at a dinner party. Get to them before that happens. Neither is your best first book, but make them your third and fourth.

2. Save the last cases for last. Curtain is Poirot's final case and Sleeping Murder is Miss Marple's. She wrote them both years ahead and meant them to come at the end. Let them.

3. Otherwise, any order will do. Almost every book stands on its own. A few of the Poirots mention earlier cases in passing, so if you are the sort of person who reads the last page first, go in order of publication. If you are the sort of person who reads the last page first, please stop that.

4. Try the short stories. For a reader who isn't sure about a whole novel, the stories are a fine way in. For Poirot, Poirot Investigates (1924). For Miss Marple, The Thirteen Problems (1932), which came out over here as The Tuesday Club Murders, a village circle trading unsolved mysteries after dinner. Thirteen bites, and you'll know whether you like her.

5. Don't start at the end of her career. The very late books, from the seventies, were written when she was past eighty, and you can tell. They have their admirers. Make their acquaintance after you've fallen for her, not before.

For a young person, twelve and up. The ABC Murders, then Murder on the Orient Express. My granddaughter Patricia, who is thirteen, read the first one in a single sitting this July on my porch and asked for the second before supper. I keep a shelf of spares for exactly this reason.

For someone who likes a love story. Death on the Nile. There's a great deal of love in it, of several kinds, and a good deal of trouble.

For someone who thinks mysteries are silly. Five Little Pigs. It is a serious novel about memory and regret that happens to have a murder in it. I have converted two English teachers with it.

For someone who only knows the television versions. Pick the book of your favorite episode and read it. You'll be surprised how much the books hold that even the best adaptation has to leave out.

For someone with tired eyes. Nearly all of her books are in large print at the public library. Ask. That's what we're there for.

For a lover of adventure, not puzzles. Try Tommy and Tuppence, her third pair of detectives, a bright young couple who start in The Secret Adversary (1922) looking for work and find a great deal more. They are not her best, but they are great fun.