The history of constant‐level balloons as observational platforms for atmospheric research is reviewed. Recent experience in using simple tetroons with Global Positioning System transponders for long‐range tracking during the Atlantic Stratocumulus Transition Experiment (ASTEX) is presented, along with an overview of the results of the ASTEX/Marine Aerosol and Gas Exchange Lagrangian strategy experiments. Progress in balloon materials and tracking capabilities is discussed, and a design is presented for an economical, lightweight “smart balloon” for use in future Lagrangian strategy, atmospheric chemistry experiments.