This dissertation investigates how top management team (TMT) members shape strategic decision-making in the corporate finance context, drawing on Upper Echelons Theory (UET) as its theoretical foundation. While behavioral perspectives have long established that senior executives exert meaningful influence on organizational outcomes, corporate finance research continues to rely on frameworks with insufficient behavioral foundations, a gap this work seeks to address. The dissertation comprises three interrelated research manuscripts. The first examines how Chief Financial Officers with greater managerial power contribute to value creation in mergers and acquisitions. The second and third manuscripts shift focus to CEOs, exploring how narcissistic tendencies drive the use of impression management in M&A contexts and how this relationship is moderated by the degree of communication constraints executives face. Together, the manuscripts advance understanding of both functional TMT members and CEO psychology as drivers of corporate strategic behavior, enriching theoretical frameworks at the intersection of strategic management and corporate finance.