Our first call for papers teasingly stated that "There's more to uncertainty than probabilities" and set out to convince you that ISIPTA 2019 is a good place for discussing such matters. If you did not receive our first call, or are still undecided about submitting a paper or a poster, then let the features below convince you. We would like to highlight the paper submission deadline (1 March), the availability of grants for attendees with limited funding, and the announcement of our three keynote speakers: Thomas Dietterich, Vladimir Vovk and Aharon Ben-Tal. Basic info: ISIPTA 2019 is the 20-year anniversary edition of the world's main forum on imprecise probabilities. It takes place in Ghent, Belgium, from 3 to 6 July 2019. All details are available at http://isipta2019.ugent.be. Scope: The ISIPTA conferences are devoted to robustness and imprecision in uncertainty modelling, inference and decision making, focusing in particular on uncertainty frameworks that extend or replace the probabilistic one. Invited speakers: ISIPTA 2019 will feature keynote talks by Thomas Dietterich, Vladimir Vovk and Aharon Ben-Tal, respectively on robust AI, game-theoretic probability and robust optimization, and how these relate to imprecise probabilities. Additionally, on the occasion of ISIPTA's 20-year anniversary, four former presidents of the Society for Imprecise Probability will give invited talks on topics close to their hearts. Concept: Each accepted contribution is presented and discussed, in two separate sessions. Presentations are short and always plenary. Detailed explanations and discussions are face-to-face, typically with the aid of a poster, a flipchart, or some other medium of your choice. Atmosphere: ISIPTA conferences are characterised by a friendly and cooperative style, a strong emphasis on in-depth discussion and openness to new ideas. We hope that you too will enjoy and contribute to this unique atmosphere. Venue: Ghent has been called "Belgium's best kept secret" by the Lonely Planet travel guide and a "medieval masterpiece" by The Guardian. The conference itself takes place in an old Augustinian monastery, situated in its historic city centre. Social programme: In order to blow off the accumulated academic steam, the programme also features several social activities, such as an opening reception at the town hall, a guided boat trip along the city centre canals, and a conference dinner with regional specialties, including some of our excellent Belgian beers. Types of contributions: We accept long papers, short papers and poster abstracts. Papers are published in a volume of PMLR, unless explicitly preferred otherwise by their authors. In order to give you some leeway, we have moved the paper submission deadline back by two weeks: the final and hard deadline is the 1st of March. Poster abstracts, however, can be submitted until a couple of weeks before the conference, but will not appear in PMLR. Grants: For researchers who would like to attend ISIPTA 2019, but are unable to do so due to budget constraints, we now have grants available to cover (part of) the costs. Preference will be given to PhD students, but the grants are also open to more senior researchers. Information on how to apply is available on our website. We look forward to receiving your contribution and to seeing you in Ghent. The ISIPTA 2019 Steering Committee and PC board F. Cozman (University of Sao Paulo, Brazil) J. De Bock (Ghent University, Belgium) G. de Cooman (Ghent University, Belgium) C. de Campos (Utrecht University, The Netherlands) E. Quaeghebeur (Delft University of Technology, The Netherlands) T. Seidenfeld (Carnegie Mellon University, USA) G. Wheeler (Frankfurt School of Finance and Management, Germany)