The aim of CLOUD-MOTION is to establish a network of early stage researchers (ESRs, all PhD students) at 10 institutions across Europe. The role of aerosol nucleation and ice nucleation for atmospheric aerosol, clouds and climate is investigated. The focus of investigations is on a) aerosol nucleation and growth in pristine environments (tropical free troposphere and unpolluted marine environments), b) aerosol nucleation and growth in the anthropogenically polluted atmosphere (urban environments), c) the formation of ice on glassy Secondary Organic Aerosol acting as Ice Nucleating Particles (“glassy SOA as INP”). The major research activity of the network will be three sets of joint experiments carried out at the CLOUD aerosol chamber at CERN to which all ESRs contribute. At the CLOUD chamber nucleation experiments are performed at an unprecedented level of precision and completeness using highly innovative instrumentation. A well-structured research and training plan is set up for every ESR as well as a comprehensive, quality-controlled supervision. A high-quality PhD training is arranged. The ESRs are brought together for network training events such as summer schools and workshops for integral data analysis. Courses by world leading experts are taught spanning from general atmospheric aerosol chemistry and physics to specialized sessions. The summer schools and workshops are specifically tailored to the needs of the trainees. Transferable skills training includes courses on scientific writing, presenting talks, interaction with media, entrepreneurship, IPR, and management. The partners from the private sector (2 beneficiaries, 2 partners) are closely integrated in the action.