Electronic monitoring systems (EM, sometimes known as remote electronic monitoring or REM) have been put forward since the 1990s as a promising solution to fisheries monitoring and data collection challenges. These systems, which produce, store, and in some cases transmit video, location, and sensor data, allow fisheries managers to remotely ‘see’ the activities of individual fishing vessels and entire fleets. Governmental, non-governmental, and corporate actors are rallying behind EM as a key tool for achieving sustainable fisheries, touting their benefits over existing fisheries monitoring approaches using logbooks and human observers. A sizable gap exists, however, between the discursive prominence of EM in fisheries governance fora and operational realities. In the global fishing fleet, coverage by EM systems is a drop in the ocean. Like other private sector-led environmental interventions, EM derives its allure from promises of effectiveness, efficiency, transparency, and scalability in service of a more desirable future, even as it faces myriad implementation challenges in the present. In this presentation, I critically assess the promise and functioning of electronic monitoring systems, with particular attention to the monitoring of seabird bycatch in fisheries. Drawing on interviews with marine ecologists, fisheries policy experts, and technology providers, and document analysis of published research and technical reports, I outline the tensions and obstacles facing EM at three key stages: upstream of implementation, on-board fishing vessels, and downstream data analysis. Although promoted as technologies of transparency, I show how this transparency is selective: at each stage, various interventions aim to maintain business-as-usual. Rather than argue for a more powerful, top-down model to overcome this selectiveness, the presentation makes the case for understanding the failures of EM in the context of wider relations of power and knowledge in fisheries governance and challenges transparency as a necessarily ‘good’ normative ambition for ocean governance.