Back in 2003, Starbuck’s put together a team led by Peter Dukes, a product manager in the company's espresso division. Their mission? To develop a seasonal drink, similar to the Eggnog Latte and Peppermint Mocha they had created before, to add to the fall lineup. After spending a day eating pumpkin pie and sipping coffee, they decided to focus their efforts on a pumpkin-inspired beverage. The idea wasn't especially popular among customers the company surveyed online, but the team endorsed it anyway.

Developers tested ten products with consumers, with the Pumpkin Spice Latte (or PSL) coming out in the middle of the group after chocolate and caramel flavors. Nevertheless, there was something special around the pumpkin flavor, as there wasn't anything else like it available at the time. The company spent months crafting different versions of the drink, eventually coming up with a perfect blend of cinnamon, clove, and nutmeg to infuse the espresso and steamed milk, then began experimenting with different combinations and ratios of pumpkin to spice. (Ironically, they ultimately decided on a recipe without pumpkin; just the spice.)

The PSL appeared on menus for the first time in the fall of 2003; but only in two cities. Starbucks rolled it out in just 100 stores in Vancouver, British Columbia, and Washington, D. C. It was an unqualified success, and the next year, the PSL made its nationwide debut. It has since become the brand's most popular seasonal drink of all time.

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