Pfizer is one of Ireland's leading employers and the largest pharmaceutical sector investor and employer. One of the first pharmaceutical companies to locate in Ireland (1969), Pfizer has a rich heritage of innovation and expansion over a forty-year period. There are approximately 5,000 colleagues across 4 Irish locations based in Cork, Dublin, and Kildare. Total capital investment by the company in Ireland exceeds $10 billion. Pfizer's business interests in Ireland are diverse and include manufacturing, shared services, R&D, treasury and commercial operations.

Ireland is a leading manufacturing base for Pfizer globally, exporting to global markets. There is a manufacturing presence in Active Pharmaceutical Ingredients, Solid Dose Pharmaceuticals, Sterile Injectables, Vaccines and Biopharmaceuticals. Many of Pfizer's leading and newest medicines are manufactured for global export from Irish sites. Part of Pfizer's Worldwide Research & Development (WR&D) is based in Ireland - the Global Biotherapeutics Technology group at Grange Castle was established in 2006 and is part of a world-leading protein drug discovery unit within Pfizer Worldwide R&D.