This article examines the nexus of ecological science and environmental politics by considering the tensions between the global circulation of the notion of “environmental monitoring” and the local production of data on environmental change. The history of the planning of the Global Network of Environmental Monitoring (GNEM) program provides a glimpse of what it takes to launch a program of environmental monitoring globally on the level of intergovernmental organizations, such as the United Nations. The first part of the paper traces the GNEM project as it moved through different international agencies and international programs in the 1960s and 1970s. The second part explores the local story of the environmental monitoring of Lake Baikal. The emergence of “environmental monitoring” as an issue of global concern, and the local story of environmental monitoring of Lake Baikal were interrelated, but only in theory: Rather than boosting the already ongoing local monitoring of Lake Baikal, the intergovernmental global monitoring program was used as a legitimation to sustain the environmental pollution of the lake. Yet, the Soviet scientists-led environmental activism, which failed to influence environmental regulation in the Soviet Union, had critically contributed to the sustaining of the environmental monitoring programs in a small way, through collecting the data detailing the environmental changes in the places most affected by disastrous Soviet environmental policies, such as those regarding Lake Baikal.