From an extensive profile:
"This was familiar territory for Shotwell. The 54-year-old engineer has worked with Musk since SpaceX’s founding in 2002, longer than almost any executive at any Musk company. She manages about 6,000 SpaceX employees and translates her boss’s far-out ideas into sustainable businesses—whether it means selling customers on a rocket or telling them not to read too much into @elonmusk.SpaceX’s Secret Weapon Is Gwynne Shotwell -- Bloomberg
She’s succeeded remarkably. In fact, SpaceX, the business, might be as impressive as SpaceX, the showcase for Muskian wizardry. The company is privately held—Musk owns a majority stake, alongside investors such as Google, Fidelity Investments, and Founders Fund—and doesn’t disclose revenue. But last year its workhorse Falcon 9 rocket reached orbit 18 times, more than any other launch vehicle in the world. SpaceX, which now has more than half of the global launch market, has signaled it would do about 30 launches in 2018, including at least one more Falcon Heavy launch later in the year. The company is worth $28 billion, making it the third most valuable venture-backed startup in the U.S., after Uber Technologies Inc. and Airbnb Inc."