At M&Co. in the 1990s, you were largely responsible, with your husband Tibor Kalman, for a collection of very quirky products that found a huge market and consumed a large amount of your time. How did the watches and clocks with skewed numbers and conceptual faces and the folded paper paperweights come about?

Tibor was the driving force. He had incredible momentum, a million ideas, and great pragmatism. The designers at M&Co. worked like crazy. And what did I do? I was half in the background, half in the clouds, and working with Tibor all the time. I mean all the time. We never stopped thinking about ideas and projects. The watches were just, "How would it be interesting to play with how people see time?" The paperweights were more "aha!" Tibor sketched his ideas on yellow legal pads. If he did not like something, he ripped the page off the pad, crumpled it up, and threw it on the floor. He looked around one day and said, "That's it." He had invented a paperweight. There were many styles (blueprint, music). After Tibor died, I created the Prozac paperweight, which was a list of all the antidepressants people took. I thought every therapist would want one.

Now you're doing more products on your own?

Now I have ideas, and I understand how difficult it is to realize something new. I designed a dog raincoat out of plastic bags for my dog. I took it to Kate Spade. They designed a real coat and that expanded into people raincoats and bags and journals. It brought a beautiful income for a few years. But I would never have done it on my own. I much prefer to go to someone with the production capabilities. But actually, apart from a random idea every once in a while, I don't drive myself to create new products.

M&Co. was eventually sold, and others started making the products. At that time, you more seriously turned to children's books and illustration. But even this seems somewhat entrepreneurial. What prompted the creative turn of events?

The books were a natural development. I had stopped writing, and it was time to begin again. Of course, I had to find a publisher and then an agent. But this business of making books is a grand one.

So many of your projects come from such a fresh, unfettered, and noncommercial place. Yet they have legs in the marketplace. The Elements of Style book is not necessarily something one would think could have commercial success, but it certainly has cultural props. How did this come about? When did you conceive the idea of an opera based on it? And is there more you're going to do with it?

The Elements of Style happened because I was in Cape Cod on vacation poking about a church rummage sale. I was by the sea, where my brain was getting extra oxygen. And the idea was obvious and immediate. It took a few years to convince the parties—the E.B. White estate, the publisher, and so on. But it was a great publishing success and I loved working on it with absolutely no one telling me what to do.

I then contacted Nico Muhly, who I have known for years. He is a fantastically wonderful composer. And we worked together on what this small night of music would be. I wanted to perform it in an unconventional space, and luckily Paul Holdengraber of the New York Public Library agreed to let us have the main reading room. These things all seem obvious to me. But he was brave. After all, I said to him, "A bunch of my friends and I want to bang some cans in the library reading room. Okay?" It was a spectacular night.

In the Maria Kalman universe, are there other entrepreneurial ventures that are on the boards waiting to be launched?

"The Principles of Uncertainty," which was an illustrated column for the New York Times Select, and now a book, will hopefully be an opera of some sort. But this takes time, and I am not sure what will happen. And I am thinking about making little movies and performance things. The point would be to get carried away with something interesting and fun that would come naturally.

How do you get your ideas?

I don't like to force ideas, just hope that they come. And I would like to have a little shop. Maybe in one of those stupendous metal coffee carts that sit on the corners in New York. I could see having a little business that I ran from there, with odd stuff and odd hours.