Data from small satellites are rapidly converging with high-speed, high-volume computational analytics. “Small satellites, big data” (SSBD) changes the ability of decision-makers to persistently see and address an array of international security challenges. An analysis of these technologies shows how they can support decisions to protect or advance national and commercial interests by detecting, attributing, and classifying harmful, hostile, or unlawful maritime activities. How might the military, law enforcement, and intelligence communities respond to maritime threats if these new technologies eliminate anonymity at sea? The emerging evidence presented on maritime activities is intertwined with national security (e.g., territorial and resource claims, sanctions violations, and terrorist attacks), legal and illicit businesses (e.g., illegal fishing, trafficking, and piracy), and other concerns (e.g., shipping and transit, chokepoints, and environmental damage). The ability of SSBD technologies to observe and catch wrongdoing is important for governments as well as the commercial, academic, and nongovernmental sectors that have vested interests in maritime security, sustainable oceans, and the rule of law at sea. But findings indicate that transparency alone is unlikely to deter misconduct or change the behavior of powerful states.