Fadell sold his company a year ago to Google (GOOG) for $3.2 billion but agreed to continue running it. Nest makes Internet-connected thermostats and smoke detectors. Following its acquisition by Google, Nest acquired connected camera maker Dropcam for $555 million.

Fadell will oversee the group responsible for Google Glass, the $1,500 wearable computer mounted on an eyeglass frame. (Glass has been widely mocked in San Francisco and elsewhere and gave rise to the term “Glasshole,” used to describe a person so enamored with new technology that they ignore the world around them.) The unit is run by Ivy Ross, who reports to Fadell. A former Apple (AAPL) executive most closely associated with the creation of the iPod, Fadell is not relinquishing his responsibilities at Nest, which he co-founded in 2010 with Matt Rogers, his former intern at Apple. Glass will remain within Google and not become a part of Nest.

The new duties mark an interesting turn of events for Fadell, who has surprised some observers by remaining with Google following his company’s acquisition, which made him a billionaire. Responsibility for such a high-profile project—and one closely associated with Google co-founder Sergey Brin—confirms Fadell’s position as trusted advisor to CEO Larry Page.

As for Glass, the group expects to wind down its nearly two-year-old Explorer program in the coming months as it continues work on the next generation of the product. Though some reports suggest that the product has lost momentum, Google maintains that its graduation from Google X is a positive sign and a step toward commercial viability.

Learn more about Google’s Glass from Fortune’s video team: