  We briefly discuss models of energetic particle acceleration by supernova
shock in active starforming regions at different stages of their evolution.
Strong shocks may strongly amplify magnetic fields due to cosmic ray driven
instabilities. We discuss the magnetic field amplification emphasizing the role
of the long-wavelength instabilities. Supernova shock propagating in the
vicinity of a powerful stellar wind in a young stellar cluster is argued to
increase the maximal CR energies at a given evolution stage of supernova
remnant (SNR) and can convert a sizeable fraction of the kinetic energy release
into energetic particles.
