WeWork has long been a place for small startups and solo entrepreneurs to grab a desk and get to work, all with the flexibility of month-to-month payment. But today has signed on a rather huge client in the form of Microsoft.

WeWork and Microsoft are starting the “City as a Campus” partnership, which gives 300 of MSFT’s global sales and marketing team total access to all of WeWork’s Manhattan locations, communities and services.

This is interesting considering that Microsoft has a New York office, out of which its sales team could work.

The idea here is that sales people, in particular, work and sell in a very mobile way, taking numerous client meetings across the city in a single day. Microsoft’s GM of Office Marketing Matt Donovan believes that this will increase productivity and efficiency in the Global sales and marketing team, letting them touch down in any of WeWork’s locations to get some work done in between meetings.

“You can imagine a future where all people in enterprises are working in the types of spaces that WeWork provides, with all the flexibility that entails,” said Donovan. “We’re starting that future early with Microsoft.”

This isn’t the first deal Microsoft and WeWork have struck. The companies previously signed a partnership that gives all WeWork members access to MS Office.

The Microsoft-WeWork partnership starts as a pilot with 300 Microsoft employees, but may indeed grow into something bigger. As part of the deal, Microsoft will also be getting similar ‘touch down’ spaces for its sales teams in Philadelphia and Portland, as well as a bulk desk deal to move Microsoft’s Atlanta-based Advertising team into WeWork Buckhead.

WeWork’s Chief Product Officer Dave Fano said that WeWork has been on the path toward bringing in larger corporations for a while, and is now ready to support a group of 300 Microsoft employees moving flexibly between its locations.

Part of the preparation included having the inventory, as well as ensuring that any given WeWork location could function as an office for a Microsoft employee, including all the tedious stuff like access to intranet. He also added that big companies, just like small ones, need flexibility when it comes to work space.

“They don’t know how they’re going to grow or if they’ll shrink and be spending money on unused space, which can be costly when these companies go into two- or three-year leases,” said Fano. “WeWork can solve for that with the same financial flexibility that we offer smaller companies.”

As a part of this new partnership, Microsoft can also test new products and services within the WeWork community. That starts with actual WeWork employees but could eventually extend to WeWork members, as well.