Sitecore Experience Accelerator, or SXA, is a toolkit for building sites faster. It gives you ready-made components, page designs and a shared grid, so teams can assemble pages without writing new code each time.
SXA supports multiple sites on one Sitecore instance. Marketers can reuse layouts and themes, while developers extend the component library when needed.
It works well when several brands or regions need consistent pages with local control.
We use SXA when it fits the project, as described on our Sitecore page.