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Experiments have been carried out to characterize the geometry of the neck which forms during the cold drawing of poly (methyl methacrylate). Sequence photography was used in conjunction with tensile stress‐strain measurements. A series of tests were carried out at various temperatures, strain rates, and amounts of molecular preorientation to determine the effect of each of these variables on neck geometry. It was found that: (1) The neck geometry does not stabilize at the point where the load first reaches its steady‐state value, but at an elongation much beyond this point. (2) As the applied strain rate is increased, the steepness of the neck shoulder passes through a maximum. Further increase in the strain rate causes the neck to become more diffuse. (3) A similar maximum in neck sharpness is observed vs temperature. (4) Preorientation drastically reduces the tendency for yielding to become localized in a well‐defined neck. By combining neck‐profile photographs and load‐extension curves during drawing, it was possible to construct a series of ``true'' stress‐strain curves for poly (methyl methacrylate) at various temperatures, strain rates, and degrees of molecular preorientation, which should represent very closely the homogeneous stress‐strain characteristics of the material itself.