PW: You've been designing clothing since the 1960s. Why did you wait so long to write a book [Essentially Lilly]?

I thought the idea of writing a book was appalling. I'm a private person. I hate anything having to do with advertising and publicity. I was just happy doing what I was doing. But my friends and colleagues thought my story should come out. Thank God for Jay, who made it come out very easily. We sat under the palm trees around the pool at my home in Palm Beach and thought about how to replicate this lifestyle on the printed page.

Why is the book primarily about entertaining, not fashion or style?

The clothes are part of the armor that Lilly has. Lilly is revered as a hostess in Palm Beach, and she does it all. For a large section of big society, this book is like the literary equivalent of comfort food. It's about bringing the same joyous and colorful life of the clothes to life.

This book is really about going with the flow. If you've got 10 matching plates, that's great, if you don't, it doesn't really matter. It's not so much dictating how you do something, rather it's "try this. Have fun and relax." The clothes are a way of life, so this is a way of life type of book!

Why has preppy style always seemed to stay in vogue among certain crowds?

It's so simple, and so comfortable. It really does make you smile.

Preppy style is for people who know who they are. You can slip on Lilly's dresses and you can go anywhere. In Palm Beach, four out of five people are wearing Lilly.

God bless them!

Your designs have come to embody an entire culture. Did you have any idea your dresses would make such an impact when you first started?

Absolutely not! I fell into it, and then I just had to keep going. It got to be more and more fun. There was no foresight, no anything, thank God.

What's one of your favorite memories of entertaining at your home in Palm Beach?

One time years ago, we had about 25 people coming for dinner. Among the guests were Estée Lauder and her husband. My husband, Enrique, was mortified when I said, "Okay, Mrs. Lauder, you can help me in the kitchen, and Mr. Lauder, you can become the bartender!" He was fabulous. He went right to it, and made everyone drinks. It broke the ice.

Who do you think will buy this book?

Lilly dresses are ageless. They are worn by women from ages three to 93.

They are so popular. There is a bunch of people who are just cultish about the dresses! People who admire Christopher Lowell, Martha and Ralph Lauren will flock to this. What Lilly offers is a happy life, and I think people will look at the book and say, "I want to be a part of it." Lilly is a very chic version of Mother Earth. People flock to her!

Oh, Jay, do stop!