  Fast Magnetic Reconnection is currently regarded as an important process also
beyond the solar system, specially in magnetically dominated regions of
galactic and extragalactic sources like the surrounds of black holes and
relativistic jets. In this lecture we discuss briefly the theory of fast
magnetic reconnection, specially when driven by turbulence which is very
frequent in Astrophysical flows, and its implications for relativistic particle
acceleration. Then we discuss these processes in the context of the sources
above, showing recent analytical and multidimensional numerical MHD studies
that indicate that fast reconnection can be a powerful process to accelerate
particles to relativistic velocities, produce the associated high energy
non-thermal emission, and account for efficient conversion of magnetic into
kinetic energy in these flows.
