We are employing fluorescence spectroscopy as a tool to monitor polymer processing parameters which are important for understanding process behavior. The measurements involve the detection of fluorescence spectra from fluorescent dyes which have been doped into the processed polymer material. The character of the fluorescence, i.e. its intensity, polarization, and wavelength distribution, yields information about the state of the polymer matrix. We have concentrated on developing concepts and methods to measure molecular orientation, shear stress, shear rate, non-Newtonian viscosity, velocity, residence time distribution, flow instabilities, quality-of-mix of ingredients, and intersegmental mixing. Work on each of these measurement problems is ongoing and in various stages of development.1-2 In this paper, we describe some recent work on quality-of-mix and intersegmental mixing.