The case for real-time, high-frequency measurement networks is very strong, and AGAGE observations and their interpretation are recognized widely for their importance to ozone depletion and climate change studies—and to verification issues arising from the Montreal Protocol (ozone) and Paris Agreement (climate) Protocols. AGAGE is distinguished by its capability to measure globally, at high frequency, all the important species in the Montreal Protocol and non-CO₂ gases in the Paris Agreement. Among the project’s scientific objectives are to: measure accurately the temporal and spatial distributions of anthropogenic gases that contribute the majority of reactive halogen to the stratosphere and/or are strong infrared absorbers; measure accurately the global distributions and temporal behaviors and determine sources and sinks of non-CO₂ biogenic-anthropogenic gases important to climate change and/or ozone depletion; identify new long-lived greenhouse and ozone-depleting gases.