The "Global Helioseismology" network activity will coordinate the exchange of knowledge concerning the global properties of the Sun. The Network Activity will link groups working on the field of stellar modelling with groups working on the investigation of global solar properties. Large amounts of global helioseismology data from various instruments are accessible; new data from SDO, PICARD and other missions will become available during the Network lifetime. The Network Activity will coordinate the process of developing methods and software for analyzing these data in the context of global helioseismology.

The "Local Helioseismology" network activity aims on exchanging knowledge and data for tests, comparisons and analysis. The activity will coordinate the process of developing common software tools and facilitate the preparation for the SDO (Solar Dynamics Observatory) and Solar Orbiter missions. This will prepare the European local helioseismology to the advent of SDO and the definition of Solar Orbiter.

The "Asteroseismology” network activity will promote a vital exchange between groups acting on the field of stellar physics. The institutions will collaborate to work on the theoretical description of physical properties of stars and to analyse and interpret stellar oscillation data.

The activity "Public Outreach" organises the dissemination of the results obtained by HELAS to all relevant levels of the educational system and to the general public in the participating countries, as well as the scientific community, in order to communicate the excitement and importance of helio- and asteroseismology at all levels. Outreach material (text, images, animations, full presentations) will be made available by the HELAS partners as well as lecture notes for teaching stellar evolution, stellar pulsations, helioseismology and asteroseismology at the university level.