FIRE may stand for:

• Foundation for Individual Rights in Education, a civil liberties organization
• Fully Integrated Robotised Engine, a model of engine produced by Fiat
• Future Internet Research and Experimentation
• Finnish Intelligence Research Establishment, a Finnish signals intelligence unit
• FIRE economy, a segment of the stock market: Finance, Insurance, Real Estate
• Fellowship of Independent Reformed Evangelicals, a network of Reformed Baptist churches

Fire is the rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition.