How do economies change? The entire history of economic progress can be recapitulated in the four-stage evolution of the birthday cake. As a vestige of the agrarian economy, mothers made birthday cakes from scratch, mixing farm commodities (flour, sugar, butter, and eggs) that together cost mere dimes. As the goods-based industrial economy advanced, moms paid a dollar or two to Betty Crocker for premixed ingredients. Later, when the service economy took hold, busy parents ordered cakes from the bakery or grocery store, which, at $10 or $15, cost ten times as much as the packaged ingredients. Now, in the time-starved 1990s, parents neither make the birthday cake nor even throw the party. Instead, they spend $100 or more to “outsource” the entire event to Chuck E. Cheese’s, the Discovery Zone, the Mining Company, or some other business that stages a memorable event for the kids—and often throws in the cake for free. Welcome to the emerging experience economy.

A version of this article appeared in the July–August 1998 issue of Harvard Business Review.