  Cygnus X-3 is a unique microquasar which shows X-ray state changes, strong
radio emission, and relativistic jets. It is also an unusual X-ray binary with
the mass-donating companion being a high mass star Wolf-Rayet but the orbital
modulation (as inferred from X-ray emission) is only 4.8 hours, a value more
common in low-mass systems. It has recently been shown by AGILE and Fermi that
Cygnus X-3, is a transient gamma-ray source (>100 MeV).
  To understand the environment, nature, and behavior of Cygnus X-3
multi-wavelength observations are necessary. In this proceedings we present the
results achieved so far from multi-wavelength campaigns.
