  The energy-energy correlation (EEC) between two detectors in $e^+e^-$
annihilation was computed analytically at leading order in QCD almost 40 years
ago, and numerically at next-to-leading order (NLO) starting in the 1980s. We
present the first analytical result for the EEC at NLO, which is remarkably
simple, and facilitates analytical study of the perturbative structure of the
EEC. We provide the expansion of EEC in the collinear and back-to-back regions
through to next-to-leading power, information which should aid resummation in
these regions.
