I spotted the frog as soon as Shelly Lazarus, chief executive of the Ogilvy & Mather Worldwide advertising agency, joined me for breakfast at her hotel in Paris. It wasn't a real frog, of course. It was made of jewels - the centrepiece of a small brooch that sat tastefully on the earth tones of her buttoned-to-the-neck trouser suit.

I had spent the previous night reading press clippings about Lazarus, and the stories often began with descriptions of the toy frogs that decorate her New York office. Frogs came into her life by accident, she likes to say, after she gave a furry one to her husband, a prominent paediatrician, as a gift. He reciprocated, and then everyone got in on the act. Her office filled up with frogs - scores of them.