Isolated photons at HERA

This contribution describes two recent measurements of isolated photons appearing in photoproduction (measured by ZEUS) and deep inelastic scattering (measured by H1) at the ep collider HERA. 1. Introduction Isolated photons with high transverse momentum in the final state are a sensitive probe of the dynamics of the hard sub-process, since they are largely insensitive to hadronisation and fragmentation and carry unaltered information of the hard scatter. Also, a good understanding of the Standard Model production mechanism of photons is especially important for new physics searches at hadron colliders, where new particle decays to photons have to be separated from the background induced by photons produced in the primary scattering processes.