The book contains courses taught to a public of Ph. D. students, post-docs and con?rmed researchers in all ?elds of heliospheric plasma physics. It aims at identifying physical issues which are common to two di?erent ?elds of astr- omy: solar and magnetospheric physics. Emphasis is given to basic processes of transport and conversion of energy: magnetic reconnection is discussed in detail from the viewpoints of MHD and kinetic physics. Processes of charged particle acceleration are reviewed and confronted with recent observations. The subject is introduced by a summary of MHD and the basic...