The High Energy Phenomena in Relativistic Outflows (HEPRO) conference series are devoted to the discussion of the latest and more relevant observational, phenomenological, and theoretical developments in the field of high-energy astrophysics related to systems displaying relativistic winds and jets. The next edition will take place in Barcelona on July 9-12, 2019.The registration period is from February 15th to May 31st 2019.More information here.