Stack Overflow for Teams is a private version of Stack Overflow, to help teams collaborate, move faster, and share knowledge amongst themselves in a secure environment. There are three tiers - Basic, Business, and Enterprise. You can compare the tiers to see which is the best fit for you on the plans page.
All tiers have the same Q&A user experience and community elements. Business and Enterprise tiers offer additional features like support for SSO, reporting, and integration with other tools and systems.
If you prefer a more public-facing site, we have 150+ sites to help support your developer community. But if you cannot find a Stack Exchange site in your area of interest, we have a place where you can propose one. "Area 51" is a community-driven process where groups of experts come together to build new Q&A sites that work just like Stack Overflow. You can read more about the site proposal process here.