In this work, PET films were stretched on the long extensional tester at various temperatures, stretch speeds, and stretch ratios. The stretched films were then characterized using various techniques. Prediction of container properties using the data generated for films was undertaken and three different approaches were used. The first method involves the use of timetemperature superposition to extrapolate the film data to the extension rate and extension ratio encountered in bottle blowing. In the second method, correlations developed between functional properties and average orientation functions for films were used for prediction of properties of blown containers. The third method was a combination of the first two methods. The birefringence was obtained by superposition and other properties were predicted using the correlation between functional properties and birefringence. With the exception of tensile energy absorption, it has been shown that mechanical properties of blown containers can be predicted from film data using any of the three methods previously described. A quantitative measure of property variation through thickness can also be obtained. Using the methods developed in this work, a map of properties and processing conditions encountered in stretch blow molding can be generated and this information can be used for designing preforms and containers.