Although external hiring is a signature feature of contemporary labor markets, internal hiring continues to benefit firms and workers. Organizations benefit from high-performing internal hires who are less expensive than external hires, and workers are likely to develop skills and gain increases in responsibility while not having to move to another firm. Fully capturing these benefits, however, requires workers to be matched to open internal jobs that complement their knowledge, skills, and abilities. Recent research has shown that internal talent markets–created when firms post open jobs and invite current employees to apply–are particularly effective for generating these complementary person-job matches. While this research asserts the benefits of market-based internal hiring, the literature on internal markets is otherwise limited; there remain open questions related to how internal matches are formed, the challenges associated with forming internal matches, and how organizations might begin to overcome such challenges. This dissertation seeks to understand how internal hiring might continue to be improved through market-based processes but also highlights some potential unintended consequences of utilizing markets to facilitate internal mobility. In doing so, this dissertation contributes to recent efforts to better understand the dynamics of within-firm hiring processes and provides a more holistic picture of internal talent markets for theory and practice.