NEW YORK – Nora Roberts is so prolific she had to take up a pen name so her publisher could release more books by her each year.

“I’m a fast writer,” Roberts told The Associated Press in a rare interview. She typically releases four books a year, and has for more than four decades.

It’s not just about her speed. It’s her range, too. She’s written more than 250 books, from romantic one-offs and fantasy-themed trilogies to a police procedural series she’s been writing for three decades. The 60th book of the “In Death” series, “Bonded in Death”, is being released in February.

Roberts has left her mark on the literary world, and she has no plans to stop anytime soon. She talked about the art of writing, why she won’t have the main characters in her “In Death” series have kids, and her thoughts on the romance genre — including why she doesn’t see herself as part of it anymore.

This interview has been edited for clarity and length.

AP: You write under two different names — Nora Roberts and J.D. Robb. Why?

Roberts: I’m a fast writer.

I didn’t like the idea of taking a pseudonym until my agent said to me one day, ‘Nora, there’s Pepsi, there’s Diet Pepsi, and there’s caffeine-free Pepsi.’ And that hit home. I drink Diet Pepsi and I’ve realized it’s marketing and I could be two brands.

So I said I would do that if I could write something completely different.

AP: You’re coming out with your 60 book in the “In Death” series. You’ve been writing two books per year for the series since 1995. What is your vision for the series at this point?

Roberts: I can’t imagine ending it and I still have ideas for where they’re going next. They’re not just books about murders. They’re about interaction and relationships and the evolution of characters.

AP: Do you have an ending in mind, or was there an ending that you had in mind at one point that you’ve gone past?

Roberts: I never had an endpoint. It just sort of happened that I got to 60 books. I’m very invested in these characters. So I like to tell their stories.

AP: You’ve said that if Roarke and Eve were ever to have a child, you would see that as the end of the series because their lives would be so changed by that. Is that true?

Roberts: That is an internet truth. Children change everything. How are they going to be out there in the middle of the night chasing bad guys or working on a case or having that crazy sex?

AP: Speaking of the sex, that’s a good transition to romance as a genre. It has evolved a lot in the last couple of years. Where do you see yourself in the pantheon of that genre?

Roberts: I don’t at all. My roots are in romance and I have a lot of respect. But I don’t write romance anymore. I do write relationships.

I’ve been writing for a really long time now, and the romance genre evolves and it changes. And it did when I was working in it, and it just got to a point where I didn’t want to go where it was evolving. I wanted to go in a different direction. So my roots and foundation are there, and gratitude. But that’s not what I’m doing now.

AP: How would you describe what you’re doing now?

Roberts: I write novels. It’s that simple – suspense, thrillers, fantasy.

AP: You like to write in trilogies. Even with “In Death,” you sometimes write in threes. Why do you think that works narratively as a writer and for your audience?

Roberts: I think of it as one big book and three parts. Something has to happen that cannot be resolved until the last book. That’s when good overcomes evil. Love conquers all and whatever. But you can’t do that until book three. It’s challenging and it’s fun and I hope it’s fun for the reader, too.

AP: How many hours do you spend writing on an average day?

Roberts: Six to eight.

AP: What do you need around you when your write, or are you at a point where you could write just sitting on a rock in the water?

Roberts: I can write anywhere, anytime. I like the quiet. That’s my favorite.

AP: For “In Death,” how did you land on a futuristic police procedural?

Roberts: I really wanted to do something different, and I thought it would be fun to go into the future and imagine the world. It could be exactly what I wanted it to be. I didn’t have to build on someone else’s or make up a little town.

AP: How would you like to be remembered?

Roberts: As a good storyteller.

AP: Are you thinking of retirement at all?

Roberts: Absolutely not.

AP: What is your biggest fear?

Roberts: Not having the next idea.

AP: Do you have a favorite book of all time?

Roberts: “To Kill a Mockingbird” is probably the most perfect novel I remember. I love “Catch-22.” And “Jane Eyre.”