An emerging literature argues that street-level bureaucrats can develop and advocate for policy innovations that change policy in meaningful ways, calling this phenomenon “street-level policy entrepreneurship.” This argument is at the heart of the present special issue, which features contributions to developing the theoretical underpinnings of street-level policy entrepreneurship and empirically examining evidence for this phenomenon. While the traditional understanding of street-level bureaucrats views them as administrative functionaries, lacking motivation or resources for innovation, this new perspective recognizes that street-level officials' deep knowledge of a given policy domain and involved stakeholders uniquely positions these officials to advocate for policy innovations affecting the domain and its constituents. We urge scholars to take street-level policy entrepreneurship seriously and to examine questions at the frontiers of our knowledge about these entrepreneurial officials, including what motivates them, what strategies for policy advocacy they find most effective, and how their behaviors are shaped by different institutional contexts.