  We present a gauge-fixed M 5-brane action: a 6-dimensional field theory of a
self-interacting (0,2) tensor multiplet with 32 worldvolume supersymmetries.
The quadratic part of this action is shown to be invariant under rigid
OSp(6,2|4) superconformal symmetry, with 16 supersymmetries and 16 special
supersymmetries. We explore a deep relation between the superconformal symmetry
on the worldvolume of the brane and symmetry of the near horizon anti-de Sitter
infinite throat geometry of the M 5-brane in space-time.
