Report by the ESA-ESO Working Group on "The Herschel-ALMA Synergies"

The Herschel Satellite and the Atacama Large Millimeter Array (ALMA) are two very large sub-mm and far infrared (FIR) astronomy projects that are expected to come into operation in this decade. This report contains descriptions of these instruments, emphasising the overlaps in wavelength range and additional complementarities. A short rationale for studying sub-mm and far infrared astronomy is given. Following this, brief presentations of Herschel and ALMA are presented, with references to more detailed documents and use cases. Emphasis is placed on the synergies between these facilities, and the challenges of comparing data produced using both. Specific examples of projects are given for a number of areas of astronomical research where these facilities will lead to dramatic improvements. This report is addressed to an audience of non-specialist astronomers who may be interested in extending their areas of research by making use of Herschel and ALMA instruments.