[en] Observations of Cygnus X-3 have been carried out at 2.5--7.5 keV, 2.2μ, 8.1 GHz, and 2.7 GHz over a 2 week period. The X-ray data show the periodic structure which is typical of Cyg X-3. At times the X-ray and infrared measurements show very similar periodic structure, both in phase and in shape, while at other times the infrared data show no periodic variability. The radio fluxes were unusually low during the period of observation; both the daily average radio flux levels and the spectral index remained nearly constant