  The study of Bhabha scattering at e^+e^- colliders probes the running of the
electromagnetic coupling. After early measurements by the VENUS collaboration
at TRISTAN and the by L3 collaboration at LEP, two recent analyses have been
performed by the OPAL and L3 collaborations. The OPAL collaboration studied
high-statistics low-angle Bhabha scattering at LEP, achieving a precise
determination of the running of alpha in the region 1.8GeV^2<-Q^2<6.1GeV^2. The
L3 collaboration investigated high-energy large-angle Bhabha scattering to
first probe the region 1800GeV^2 < -Q^2 < 21600GeV^2. All measurements are
described and a global overview of their agreement with QED predictions is
given.
