PEO

PEO may stand for:


 * Parking enforcement officer, an official who issues parking tickets
 * Plasma electrolytic oxidation, a surface-treatment process for metals
 * Polyethylene oxide, alternate name for Polyethylene glycol, a polymer
 * Old Persian, ISO 639-2 and ISO 639-3 language code
 * Pancyprian Federation of Labour, an umbrella organization for trade unions in Cyprus (Παγκύπρια Εργατική Ομοσπονδία, Pankypria Ergatiki Omospondhia)
 * P.E.O. Sisterhood, an international women's organization with headquarters in North America
 * Professional employer organization, a service provider of outsourced human resource management
 * Professional Engineers Ontario, professional and regulatory organization for engineers in Ontario, Canada
 * Program executive officer, an individual, civilian or military, responsible for large scale U.S. military acquisitions
 * Programs Evaluation Office, a covert U.S. paramilitary mission in Laos in 1955-1962
 * Progressive external ophthalmoplegia, alternate term for chronic progressive external ophthalmoplegia, an eye disorder