This paper is a summary report of the ICFA Beam Dynamics Workshop Accelerators for a Higgs Factory: Linear vs. Circular (HF2012). It discusses four types of accelerators as possible candidates for a Higgs factory: linear e+e- colliders, circular e+e-
colliders, muon collider and photon colliders. The comparison includes: physics reach, performance (energy and luminosity), upgrade potential, technology maturity and readiness, and technical challenges requiring further R&D.
