This book constitutes the proceedings of the 5th International Conference on Decision Support Systems Technologies, ICDSST 2019, held in Madeira, Portugal, in May 2019. This year the conference is a EURO mini conference and therefore has a slightly different acronym: "EmC-ICDSST 2019". The EWG-DSS series of International Conference on Decision Support System Technology (ICDSST), starting with ICDSST 2015 in Belgrade, was planned to consolidate the tradition of annual events organized by the EWG-DSS in offering a platform for European and international DSS communities, comprising the academic and industrial sectors, to present state-of-the-art DSS research and developments, to discuss current challenges that surround decision-making processes, to exchange ideas about realistic and innovative solutions, and to co-develop potential business opportunities. The main topic of this year's conference was "Main Developments and Future Trends". The 11 papers presented in this volume were carefully reviewed and selected from 59 submissions. They were organized in topical sections named: decision support systems in societal issues; decision support systems in industrial and business applications; and advances in decision support systems' methods and technologies.