A mirror, in particular for a microlithographic projection exposure apparatus, has an optical effective surface and includes a substrate (11, 61, 71, 81, 91), a reflection layer system (16, 66, 76, 86, 96) for reflecting electromagnetic radiation impinging on the optical effective surface (10a, 60a, 70a, 80a, 90a), an electrode arrangement (13, 63, 73, 83) composed of a first material having a first electrical conductivity, the electrode arrangement being provided on the substrate, and a mediator layer (12, 62, 72, 82, 92) composed of a second material having a second electrical conductivity. The ratio between the first electrical conductivity and the second electrical conductivity is at least 100. The mirror also includes at least one compensation layer (88) which at least partly compensates for the influence of a thermal expansion of the electrode arrangement (83) on the deformation of the optical effective surface (80a).