This chapter discusses the evaluation of photodegradation rates in polystyrene samples which have been blended with a commercial prodegradant copolymer, Ecolyte PS2005. In view of the experience of other researchers as well as our own with polyolefin degradation testing, it seems likely that UV-A aging will become the method of choice. The infrared absorption spectra for the various blends of crystal polystyrene with Ecolyte PS for indoor and outdoor aging respectively. Half hamburger box samples were observed during their outdoor exposure in an attempt to describe the physical changes that occur. Half hamburger box samples which had been aged outdoors for 136 days were tested in a tumbling block chamber. For the recycling study, blends were prepared using conventional crystal polystyrene extruded sheet and degradable polystyrene materials. Based on experiments to date, it appears that molecular weight measurements, obtained via solution viscometry, offer the simplest accurate measurement of degradation rates in polystyrene systems.