This work deals with maximizing the productivity of our emulsion polymer reactors. Increasing productivity means manufacturing latexes with adequate monomer conversion and final properties, safely, in the shortest possible time. This translates to reduced costs and added capacity. We set out to answer the following questions : Are we getting the most productivity from our manufacturing reactors? Can we better optimize new and existing products to increase productivity? The most efficient use of our reactor time requires that we operate at the limit of our heat removal capability (with safety margins). The first step is to quantify what this capability is. One could perform many time consuming studies on each of our manufacturing reactors to identify heat transfer coefficients and rates for each product. Our alternative approach was to use an existing product as a benchmark. Experience had demonstrated that this product was at the limit of our capabilities. This benchmark product was then characterized using reaction calorimetry (Mettler Toledo RC1) and other methods. In this manner, we quickly identified an empirical maximum heat flow "ruler" against which we could evaluate existing and new products. We could now test different feed policies and be assured that we could scale them up economically. These feed policies were identified from calorimetry and pilot plant experiments and by using computer simulation models.