A young Donna is hired by Anne Klein—and winds up in the top job.

The first thing I learned when I took the job as chief assistant to Anne Klein in 1971 was that she was the boss. Yes, she had her investors, and her husband and business manager, Chip. But Anne was as much an entrepreneur as she was a designer. She controlled every aspect of her company—which clothes were sold and where, how they were presented—and everyone reported to her. I admired her strength and appreciated how much she sweated the details. Nothing was too small for her to have an opinion about, from the positioning of darts and buttons on a blouse to the coffee mugs we used in the showroom. She didn’t miss a trick.

Anne liked to design at night. Often, it would be just her, me, and a model. She’d go into a zone and fit for hours and hours, a practice I picked up from watching her. I’d pass her pins, and she would work painstakingly on the model. Because of Anne I, too, became a stickler for fit. To me, fitting is sculpture, a three-dimensional creation on a body.

Where Anne was all about silhouette, I was passionate for fabric—and she let me shop in Europe. When it came to inspiration, she’d say, “God gave you two eyes; use them!” In many ways she was like her predecessor Claire McCardell, another great American fashion icon. Neither could separate being a woman from the clothes they designed. Clothes can and should be beautiful, but they only work if you want to wear them in your everyday life.

“Donna, I plan to travel for a while,” Anne said one day in the late spring of 1972. “I need you to do holiday on your own.” With Anne away, I felt free, and my mind raced with design ideas. My collection was couture in feeling, with every piece artisanal and special. I used my favorite colors—black, white, red, and vicuña—and incorporated lots of embroidery and leather. That collection foreshadowed my future. The truth was Anne hadn’t been traveling that summer; she had breast cancer.

Right around this time, my husband Mark and I learned that I was pregnant. I couldn’t have been happier. I was going to be a mother—the thing I wanted more than anything. I fully intended to be a stay-at-home mom. Because Anne wasn’t well, I worked even longer hours than usual, heading home at midnight or later. I wanted to prepare as much as possible for my maternity leave.

While I was in labor on Long Island, Anne was at Mount Sinai in Manhattan with pneumonia—and no one was at work. Our pre-fall collection was due that very week. We spoke on the phone hospital to hospital, discussed how many buttons should be on a double-breasted navy cashmere coat.

Gabby, all of ten pounds, had no sooner popped out than our investor Gunther Oppenheim called my hospital room in that deep German voice of his: “Donna, we need you to come back to work.”

“Would you like to know if I had a boy or a girl?” I asked. “It’s a girl.”

I checked with my doctor, who forbade me to go back to work so soon.

When I told Gunther, he said, “OK, we come to you,” and less than a week later the whole staff arrived at the new house Mark and I had moved to in Lawrence, Long Island. I had the bagels and lox all spread out. I assumed they were coming to coo over Gabby and maybe bring flowers and a casserole. Then I saw the trucks arrive, the racks of clothes being wheeled up my driveway. This was business.

We cleared out my dining room so we could use it as a design studio. Betty Hanson, our head of sales, walked in and immediately answered the phone in the kitchen.

“Um, OK. Yes,” I heard her say. Her face fell. She hung up and looked all around, clearly unsure of what to say. She came closer. “Anne died.”

The shock hit me, and I started shaking and couldn’t stop. Anne died? How could that be? She was only 51. She was going to be fine. At least I thought she was. Betty knelt by my side.

“Donna, listen,” she said in a soothing voice. “This is terrible, but you need to finish the collection. The stores are waiting. Anne would have wanted you to.”

Then it dawned on me. Everyone knew. They knew all along that Anne was dying. And no one told me. I never got to say goodbye to her. She was my teacher, my mentor, my everything. I was 25 years old, had just given birth, and Anne was dead.

A whirlwind. A 24/7 storm of madness. Those are the only ways I can describe the chaotic days and weeks that followed. All my dreams of being a stay-at-home mom had gone out the window. I had to deliver the pre-fall collection, then face the big one—fall—set to show in May 1974.

I didn’t channel Anne in any way while designing that collection; I was still too numb for that. But I did call upon every lesson she taught me. I designed for flexibility, creating mix-and-match sportswear a woman could wear multiple ways. I knew I had to put my own stamp on this collection, so I made it a little hipper, a little cooler. I wanted the collection to feel young and sexy.

On the day of the show, all my usual insecurities washed over me. Who was I to take on Anne’s legacy? Would everyone laugh at me for even trying? During the presentation in our showroom, I frantically fussed over each model before I let her walk out from behind the curtain, and I held my breath until I sent out the last girl. My work was done. I felt naked, exposed, and horribly vulnerable.

Then, out of the darkness, over the music, I could hear the start of applause, and it grew and grew. The reaction was immediate and overwhelming. Someone handed me a bouquet of white roses. When I stepped out onto the runway for my bow, people stood. Blinded by the lights and the emotion, I trembled and tried not to fall over. The collection was a hit.