The User Support Department (USD) of the ESO Data Management and Operations Division is based in Garching bei München, Germany. Its main activities consist in providing support to users of ESO facilities:

• Support for Phase 1 proposal preparation, mainly concerning technical questions on instruments, strategies, etc. at the time of writing observing proposals;
• Support, review and optimization during the preparation of Phase 2 material. The purpose is to ensure that the material submitted by the users for the execution of their programmes is compliant with the principles of Service Mode observing and with the Service Mode guidelines, and that the observing strategy is both efficient and adequate for the scientific goals;
• Maintenance of a Web-based Service Mode status information service, where users can obtain up-to-date information on the progress of their Service Mode programmes.
• Operation of a helpdesk system (support.eso.org) where users can address questions and request assistance on all aspects of ESO telescope Service Mode operations.

It also provides assistance to Science Operations Teams at ESO's observatories in the areas of:

• Program mid-term scheduling and tracking services;
• Providing a link between the observatory and the users when actions are needed during the execution of service mode programmes;
• On-site assistance for the execution of Service Mode programmes;
• Maintenance of the User Portal database content;
• Definition and maintenance of operations metrics;
• Definition of requirements for observation preparation tools and feedback on operational requirements for new instruments.

The User Support Department currently provides support for all the instruments available at the VLT and VLTI (Paranal), as well as for the surveys and open time observations on VISTA and VST. Users having obtained Visitor Mode time at the La Silla telescopes (NTT, 3.6m and 2.2 m telescope) should contact the La Silla Science Operations Group directly.

The User Support Department is headed by Marina Rejkuba. The USD Phase 1 and Phase 2 support for the VLT/VLTI, VISTA and VST instruments is distributed among the USD staff astronomers as follows (in alphabetical order with the main astronomer responsible in bold):

• CRIRES: Carlo Manara, Mario van den Ancker
• ESPRESSO: John Pritchard, Markus Wittkowski
• FLAMES: John Pritchard
  
• FORS2: Henri Boffin, Christian Hummel, Paola Popesso, John Pritchard
  
• GRAVITY: Christian Hummel, Markus Wittkowski
• HAWK-I: Lowell Tacconi-Garman
  
• KMOS: Michael Hilker, Paola Popesso, Lowell Tacconi-Garman
  
• MATISSE: Christian Hummel, Markus Wittkowski
• MUSE: Henri Boffin, Michael Hilker, Carlo Manara, Monika Petr-Gotzens
• OMEGACAM: Michael Hilker, Monika Petr-Gotzens
• PIONIER: Christian Hummel, Markus Wittkowski
• SPHERE: Henri Boffin, Carlo Manara, Monika Petr-Gotzens, Mario van den Ancker
• UVES: Christian Hummel, Carlo Manara, John Pritchard
• VIRCAM: Michael Hilker, Monika Petr-Gotzens, Marina Rejkuba
  
• VISIR: Mario van den Ancker
  
• X-SHOOTER: Carlo Manara, Tommaso Marchetti (fellow), Paola Popesso, John Pritchard, Markus Wittkowski, Mario van den Ancker
  

The USD operations support scientists, Stéphane Marteau and Sangeeta Mysore, are responsible for a variety of operations tasks, including maintaining the Service Mode run status pages, managing the USD helpdesk (support.eso.org), maintaining the external report and verification modules for instrument packages implemented in the p1 and p2 web tool, and delivery of instrument specific observation preparation tools. Matheus Brito is taking care of travel arrangements for visiting astronomers.