Under its two first calls for Trans-National Access (TNA), ATMO-ACCESS (Solutions for Sustainable Access to Atmospheric Research Facilities) provided opportunities to access some of the most advanced atmospheric research facilities in Europe. These include ground-based observatories, mobile platforms, atmospheric simulation chambers, and central laboratories for analyses and calibrations. ATMO-ACCESS offers free of charge access to these facilities, including specific training in addition to the logistical, technological, and scientific support. Users may also benefit from a contribution to their travel and local subsistence costs.