Microsoft set up in the Republic in 1985 and has grown from employing just nine people, to 1,500 people based at its Leopardstown and Sandyford industrial estates.

The European Operations Centre (EOC) formed the first plank of Microsoft's Irish business. Since then it has expanded to become the manufacturing, distribution and logistics hub for a large portion of Microsoft's worldwide operations, focusing on Europe, the Middle East and Africa (EMEA). Microsoft's European product development centre was established in 1988. It specialises in software localisation for multiple markets, and recently translated the newly launched Windows 2000 operating system into 16 languages.

The Sandyford centre in Dublin has grown from localising just two products (MS-DOS and PC Word) in 1988, to more than 100 products in 27 languages.