This book constitutes the proceedings of the 6th International Conference on Decision Support Systems Technologies, ICDSST 2020, organised in Zaragoza, Spain, in May 2020. The conference was held online only due to the Corona pandemic.

Methodological Contributions.- Two Sides of Collective Decision Making - Votes from Crowd and Knowledge from Experts.- Using Multi-level DEA to go beyond the three dimensions of sustainability.- Analysis of Graphical Visualizations for Multi-Criteria Decision Making in FITradeo Method using a Decision Neuroscience Experiment.- The Multi-Actor Multi-Criteria Analysis (MAMCA): New Software and New Visualizations.- Complexity Clustering of BPMN Models: Initial Experiments with the K-means Algorithm.- Case Studies and Applications.- To Click or Not to Click? Deciding to Trust or Distrust Phishing Emails.- Management Information System to Police facility location.- An Automated Corpus Annotation Experiment in Brazilian Portuguese for Sentiment Analysis in Public Security.- An E-government procurement Decision Support System Model for Public Private Partnership projects in Egypt.- Determinants of recommendation in the airline industry: An application of online review analysis.- Artificial Intelligence Based Decision Making for Venture Capital Platform.- Supporting Operational Decisions on Desalination Plants from Process Modelling and Simulation to Monitoring and Automated Control with Machine Learning.- Overview.- DSS, BI, and Data Analytics Research: Current State and Emerging Trends (2015-2019).