  We analyze X-ray/gamma-ray observations of Cyg X-1 in the soft state. We find
the hybrid thermal/non-thermal model fits the data very well. The significant
contribution from the non-thermal electrons is required to account for the
observed power law extending without a break to at least 800 keV. The presence
of electron-positron pairs in the hot source is unlikely. We propose the
geometry in which a cold accretion disk, surrounded by a hot corona, extends
down to the last stable orbit. At the observed accretion rate the corona
ensures the stability of the cold disk.
