The major focus of this study was to understand the effects of bond coat processing on the durability of Thermal Barrier Coatings (TBCs) and use this understanding to prepare TBCs with improved performance characteristics. The system studied consisted of the single crystal superalloy Rene N5 as a substrate and yttria-stabilized zirconia as a ceramic topcoat prepared by electron beam physical vapor deposition (EB-PVD). Two general types of bond coat were studied; a platinum modified aluminide and a NiCoCrAlY overlay. This paper focuses on the platinum aluminides. The degradation behavior of the state-of-the-art systems during thermal cycling (one hour cycles in a bottom-loading furnace) was evaluated in the first stage of the study. The failure of the Pt aluminide was found to involve a combination of fracture along the TGO/ bond coat interface and a deformation mode of the bond coat known as "ratcheting". In the second stage of the study, processing methods to improve the TBC systems were utilized. These included variation of the coating thickness, Pt-content, and surface preparation (grit blasting, media polishing, etc.). Variation of the bond coat thickness and Pt-content did not produce a dramatic increase in TBC life. However, the results indicated that the surface condition of the platinum-aluminide bond coat did significantly affect TBC life and altered the failure mechanism.