The International Space Environment Service (ISES) is a permanent service of the Federations of Astronomical and Geophysical Data Analysis Services (FAGS) under the support of the International Union of Radio Science (URSI) in association with the International Astronomical Union (IAU) and the International Union of Geodesy and Geophysics (IUGG).

ISES was called IUWDS (International URSIgram and World Days Service) until 1996. The IUWDS was formed in 1962 as a combination of the former International World Days Service, initiated in 1959 as part of the IGY, and the former URSI Central Committee of USRIgrams which initiated rapid international data interchange services in 1928.

The mission of ISES is to encourage and facilitate near-real-time international monitoring and prediction of the space environment, to assist users reduce the impact of space weather on activities of human interest.