Computational Social Choice and Preference Modelling -- Aggregating Preferences Represented by Conditional Preference Networks -- Measuring Nearly Single-peakedness of an Electorate: Some New Insights -- Preference Aggregation in the Generalised Unavailable Candidate Model -- Simultaneous Elicitation of Scoring Rule and Agent Preferences for Robust Winner Determination -- Preference Elicitation -- Incremental elicitation of preferences: optimist or pessimist? -- Probabilistic Lexicographic Preference Trees -- Incremental Preference Elicitation with Bipolar Choquet Integrals -- Preference Aggregation and Voting -- In the Beginning There Were n Agents: Founding and Amending a Constitution -- Unveiling the Truth in Liquid Democracy with Misinformed Voters -- Computing Kemeny Rankings From d-Euclidean Preferences -- Iterative Deliberation via Metric Aggregation.-Manipulation in Voting -- Obvious Manipulability of Voting Rules -- Manipulation in Communication Structures of Graph-Restricted Weighted Voting Games -- Strategic Voting in Negotiating Teams -- The Nonmanipulative Vote-Deficits of Voting Rules -- Fair Division and Resource Allocation -- Allocating Indivisible Items with Minimum Dissatisfaction on Preference Graphs -- On Fairness via Picking Sequences in Allocation of Indivisible Goods -- On Reachable Assignments in Cycles -- Minimizing and balancing envy among agents using Ordered Weighted Average -- Algorithmic Decision Theory -- Interactive Optimization of Submodular Functions under Matroid Constraints -- Necessary and possible interaction in a 2-maxitive Sugeno integral model -- Coalition Formation -- Democratic Forking: Choosing Sides with Social Choice -- Hedonic Diversity Games Revisited -- Stable Matchings -- Multi-agent Reinforcement Learning for Decentralized Stable Matching -- Lazy Gale-Shapley for Many-to-One Matching with Partial Information -- Participatory Budgeting -- Participatory Funding Coordination: Model, Axioms and Rules -- Complexity of Manipulative Interference in Participatory Budgeting. .

This book constitutes the conference proceedings of the 7th International Conference on Algorithmic Decision Theory, ADT 2021, held in Toulouse, France, in November 2021. The 27 full papers presented were carefully selected from 58 submissions. The papers focus on algorithmic decision theory broadly defined, seeking to bring together researchers and practitioners coming from diverse areas of computer science, economics and operations research in order to improve the theory and practice of modern decision support.