This paper presents air-ice and ice-water drag coefficients referenced to 10-m-height winds for winter Antarctic pack ice based on measurements made from R/V Polarstern during the Winter Weddell Sea Project, 1986 (WWSP-86), and from R/V Akademik Fedorov during the Winter Weddell Gyre Study, 1989 (WWGS-89). The optimal values of the air-ice drag coefficients, made from turbulent flux measurements, are C10=(1.79¿0.06)¿10-3 for WWSP-86 and (1.45¿0.09)¿10-3 for WWGS-89. Neutral drag coefficient values are CN10=1.68¿10-3 for WWSP-86 and 1.44¿10-3 for WWGS-89. The slightly lower values for WWGS-89 reflect a smaller surface roughness (z0) attributed to the thicker snow cover present in the 1989 study region (median z¿0=0.47 mm for WWSP-86 and 0.27 mm for WWGS-89). These values are consistent with Arctic measurements for 80-100% concentration of sea ice and with those of Andreas et al. (this issue) for the Antarctic. A single (average) ice-water drag coefficient for both WWSP-86 and WWGS-89, estimated from periods of ice drift thought to represent free-drift conditions (air-ice stress balanced by ice-water drag and Coriolis force), is (1.13¿0.26)¿10-3, and the ice-water turning angle β¿=18¿18¿. This drag value is significantly lower than Arctic values for thick multiyear ice, but it is similar to the values obtained by Langleben (1982) for first-year Arctic ice. Consistent with previous findings for WWSP-86, the free-drift form of the momentum balance can be used to describe the observed WWGS-89 ice drift observations by using an ''effective'' drag coefficient and turning angle that subsume the influence of ice-ice interaction. For a typical Antarctic winter pack ice cover, it appears that the ice cover reduces the momentum flux from the atmosphere to the ocean by ~33%. ¿ American Geophysical Union 1993