The Times Square street vendors who alerted the police to a smoking Nissan Pathfinder on May 1 seemed to be acting on a combination of their streetwise instincts, their sense of civic duty, their military training and the advice of Allen Kay.

They did not know Mr. Kay personally. But they were familiar with his work.

As chairman and chief executive of the Manhattan advertising agency Korey Kay & Partners, Mr. Kay has written about half of more than 80 slogans that the company has created since its founding in 1982. The tagline for EmigrantDirect, an online banking division of Emigrant Bank — “More Money for Your Money” — was his. The one for Stuart Weitzman, the women’s shoe maker — “A Little Obsessed With Shoes” — was his, too.

Of course, the vendors who noticed the smoking Pathfinder had a different one in mind: “If You See Something, Say Something.”