If Aaron Sorkin were writing a television drama about Silicon Valley right now — let’s call it The Techplex — one of his key characters might be a product manager. He (most likely he, but maybe she) would be a good-looking, business-savvy type with an undergraduate degree in computer science, perhaps five years out of college. He’d be the “it” employee of the drama, the person at the center of a crew that would include engineers, marketers, designers, and the CEO-founder.
But what exactly would this character do?
Ask a handful of current and former product managers that question, and the most common response is “It depends.” Says Aydin Senkut, a venture capitalist and one of the first product managers at Google: “The definition is so different from company to company. That was my first title at Google because I was the first nonengineer to work on a product, and they needed a title for me.”
In fact, product managers are so hot because they are often the one person in the thick of everything, with the remit of making sure a project hits its milestones and stays on track afterward. “Really good product managers are candidates for CEO jobs,” says Mike Maples, another VC, who was a product manager at SGI and Tivoli, two tech companies from yesteryear. “They sit in the middle of a lot of things.” Adds Deep Nishar, senior vice president for products and user experience at LinkedIn: “A great product manager has the brain of an engineer, the heart of a designer, and the speech of a diplomat.”
There is a downside to the role of PMs, as they’re known in the Valley. They often have no one reporting to them, and are forced to rely instead on their cunning and sales ability to cajole colleagues from different realms of the company to work together. The PM’s actual job is to coordinate activities and make sure projects keep moving forward, causing the less impressed of their co-workers to think of product managers as glorified coordinators toting clipboards from meeting to meeting.
Yet just as the brand-manager role at Procter & Gamble launched untold numbers of careers, product management has become one of the best paths for rising through the ranks in Silicon Valley. Facebook runs a rotational product-management program that exposes young wannabe executives to multiple parts of the business. When she was at Google, Yahoo CEO Marissa Mayer created an “associate product manager” function to identify rising talent. It all makes the PM sound just about ready for primetime.
This story is from the October 28, 2013 issue of Fortune.