The application of Systems Thinking principles to Systems Engineering is synergistic, resulting in superior systems, products, and designs. However, there is little practical information available in the literature that describes how this can be done. In this paper, we analyze 12 major Systems Engineering failures involving bridges, aircraft, submarines, water supplies, automobiles, skyscrapers, and corporations and recommend Systems Thinking principles, tools, and procedures that should be applied during the first few steps of the System Engineering design process to avoid such catastrophic Systems Engineering failures in the future.