The composition of the alloy Timetal 21S has been selected as a baseline for the development of a new high temperature beta titanium alloy. A combinatorial approach employing directed laser deposition of elemental powders has been used to produce a number of test coupons that represent a controlled variation of compositions. The creep properties have been assessed using an Instron ETMT instrument operating in a constant load mode, and represented by their minimum steady-state creep rates. The microstructures have been characterized and quantified using a variety of techniques, and included in databases used to develop neural-network models for predicting minimum creep rates. In addition to the base elements (Ti, Mo, Nb, Al, and Si), neutral elements (Zr and Sn), beta-stabilizers (W), and dispersoid formers (B, C, Ge) are being explored. Based on these results, a new group of alloys for application in high temperature thermal protection systems are being developed.