International Workshop on

Logical Aspects in Multi-Agent Systems and Strategic Reasoning

Satellite Workshop of AAMAS 2021

NEWS Invited speakers are announced! Please, take a look at the related section .

NEWS Submission deadline extended to 14th February 2021.

Logics and strategic reasoning play a central role in multi-agent systems. Logics can be used, for instance, to express the agents' abilities, knowledge, and objectives. Strategic reasoning refers to algorithmic methods that allow for developing good behavior for the agents of the system. At the intersection, we find logics that can express existence of strategies or equilibria, and can be used to reason about them.

The LAMAS&SR workshop merges two international workshops: LAMAS (Logical Aspects of Multi-Agent Systems), which focuses on all kinds of logical aspects of multi-agent systems from the perspectives of artificial intelligence, computer science, and game theory, and SR (Strategic Reasoning), devoted to all aspects of strategic reasoning in formal methods and artificial intelligence.

LAMAS: The LAMAS workshop provides a meeting forum for the research community working on various logical aspects of multi-agent systems (MAS) from the perspectives of artificial intelligence, computer science, and game theory. It addresses the whole range of issues that arise in the context of using logic in MAS, from theoretical foundations to algorithmic methods and implemented tools. The workshop LAMAS has been regularly organized since 2002 and became the main annual event of the LAMAS research network.

SR: Strategic reasoning is a key topic in the multi-agent systems research area. The extensive literature in this field includes a number of logics used for reasoning about the strategic abilities of the agents in the system, but spans also game theory, decision theory or epistemic logics to name a few. The aim is to provide sound theoretical foundations and tools to tackle a variety of strategic problems in formal methods and artificial intelligence involving agents in adversarial settings. The workshop SR has been organized every year since 2013, often in co-location with the most important conferences in formal methods and artificial intelligence.

LAMAS&SR: Over the years the communities and research themes of both workshops got closer and closer, with a significant overlap in the participants and organizers of both events. For this reason, the next editions of LAMAS and SR will be unified under the same flag, formally joining the two communities.

Call for papers

LAMAS&SR is interested in all topics related to logics and strategic reasoning in multi-agent systems, from theoretical foundations to algorithmic methods and implemented tools. The topics of the workshop include, but are not limited to:

  • Logical systems for specification, analysis, and reasoning about multi-agent systems
  • Logic-based modeling of multi-agent systems
  • Dynamical multi-agent systems
  • Deductive systems and decision procedures for logics for multi-agent systems
  • Development and implementation of methods for formal verification in multi-agent systems
  • Logic-based tools for multi-agent systems
  • Logics for reasoning about strategic abilities
  • Logics for multi-agent mechanism design, verification, and synthesis
  • Logical foundations of decision theory for multi-agent systems
  • Strategic reasoning in formal verification
  • Automata theory for strategy synthesis
  • Applications and tools for cooperative and adversarial reasoning
  • Robust planning and optimization in multi-agent systems
  • Risk and uncertainty in multi-agent systems
  • Quantitative aspects in strategic reasoning


Authors are invited to submit extended abstracts of 2 pages plus 1 page for references in the AAMAS format (files here). Both published and unpublished works are welcome. Submissions are subject to a single-blind review process (submissions should not be anonymous).

There will be no formal proceedings, but accepted extended abstracts will be made available on the workshop's website. We envisage that extensions of selected papers will be invited to a journal.

Authors are invited to submit their manuscript via EasyChair.
Submission webpage:

Important dates

  • Paper submission: 10 February, 2021 (AoE) 14 February, 2021 (AoE)
  • Author Notification: 10 March, 2021
  • Camera Ready: 24 March, 2021
  • Workshop: 3-4 May, 2021

Invited Speakers

On Good-for-games automata of all sorts

Nondeterminism probably makes your favourite automata model more expressive, or at least more succinct, than determinism. However, the cost of nondeterminism is higher algorithmic complexity. Good-for-games automata, also known as history deterministic automata, are nondeterministic automata in which nondeterministic choices can be resolved on the fly, without knowledge of the future of a word. They lie in between deterministic and nondeterministic models, and combine some of the expressivity and succinctness of nondeterminism with some of the nice algorithmic properties of deterministic automata. In particular, games with winning conditions given by good-for-games automata tend to be simpler to solve than games with nondeterministic winning conditions.
In this talk, I will give an overview of good-for-games automata, survey recent developments in the area for different classes of automata (regular, pushdown, and perhaps even timed) and point to some of the hard questions that remain unanswered and some areas that remain unexplored.

Epistemic reasoning explained with the tool Hintikka's World

In this talk, we will present Dynamic Epistemic Logic which provides a framework to model epistemic situations their evolution in time. The framework is sufficiently expressive to capture public actions (e.g. broadcast of a message) but also private and semi-private actions (e.g. private messages). The framework will be explained via a software, called Hintikka’s world. We will discuss about symbolic models, which allows to represent situations with a high number of possible worlds. We then address model checking and the satisfiability problem that are standard decision problems for verifying multi-agent systems. We address epistemic planning which is undecidable in general. We will pinpoint restrictions over actions (e.g. only public actions, etc.) for which epistemic planning is decidable.


May 3

14:15  Welcome
14:30 Invited talk: Karoliina Lehtinen
On Good-for-games automata of all sorts
15:30 Break
15:45 Stephane Le Roux, Érik Martin-Dorel and Jan-Georg Smaus
Existence of Nash Equilibria in 2-Player Simultaneous Games and Priority Games Proven in Isabelle
16:05 Thomas Steeples, Julian Gutierrez and Michael Wooldridge
Mean-Payoff Games with Omega-Regular Specifications
16:25 Senthil Rajasekaran and Moshe Vardi
Nash Equilibria in Finite-Horizon Multiagent Concurrent Games
16:45 Dylan Bellier, Sophie Pinchinat and François Schwarzentruber
DQPTL: Dependency Quantified Propositional Linear-time Temporal Logic
17:05 Break
17:20 Xuefeng Wen
Democracy + Logic: Towards a General Approach to Conflict Resolution
17:40 Esteban Guerrero, Ailiana Santosa and Helena Lindgren
Causal interventions with formal argumentation theory
18:00 Francesco Belardinelli, Catalin Dima, Vadim Malvone and Ferucio Laurentiu Tiplea
A Hennessy-Milner Theorem for ATL with Imperfect Information
18:20 Wojtek Jamroga
Towards Specification of Requirements for COVID-19 Mitigation Strategies

May 4

14:30  Invited talk: François Schwarzentruber
Epistemic reasoning explained with the tool Hintikka's World
15:30 Break
15:45 Gaia Belardinelli and Rasmus K. Rendsvig.
Awareness Logic: A Kripke-based Rendition of the Heifetz-Meier-Schipper Model and a Dynamic Extension
16:05 Saúl Fernández González
Some Dynamic Extensions of Social Epistemic Logic
16:25 Munyque Mittelmann, Andreas Herzig and Laurent Perrussel
Epistemic Reasoning about Rationality and Bids in Auctions
16:45 Asta Halkjær From, Alexander Birch Jensen and Jørgen Villadsen
Formalized Soundness and Completeness of Epistemic Logic
17:05 Break
17:20 Dilian Gurov, Valentin Goranko and Edvin Lundberg
Knowledge-Based Strategies for Multi-Agent Teams Playing Against Nature
17:40 Rustam Galimullin
How Groups Can Help Coalitions
18:00 David Toluhi and Renate Schmidt
Knowledge Extraction for Multi-Agent System Communication
18:20 Discussion



Programme Committee


LAMAS&SR 2021 is co-located with AAMAS 2021 and thus follows the main conference plan to move on virtual attendance.

Previous editions

  • SR 2013, March 16-17, 2013, Rome, Italy
  • SR 2014, April 5-6, 2014, Grenoble, France
  • SR 2015, September 21-22, 2015, Oxford, U.K.
  • SR 2016, July 10, 2016, New York, U.S.A.
  • SR 2017, July 26-27, 2017, Liverpool, U.K.
  • SR 2018, July 7-8, 2018, Oxford, U.K.
  • SR 2019, August 10, 2019, Macao, China
  • SR 2020, September 7-8, 2020, Online

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