Fairness in Reinforcement Learning: A Survey
On the map: Deep reinforcement learning methods → RL for games and combinatorial optimization
Abstract (arXiv)
While our understanding of fairness in machine learning has significantly progressed, our understanding of fairness in reinforcement learning (RL) remains nascent. Most of the attention has been on fairness in one-shot classification tasks; however, real-world, RL-enabled systems (e.g., autonomous vehicles) are much more complicated in that agents operate in dynamic environments over a long period of time. To ensure the responsible development and deployment of these systems, we must better understand fairness in RL. In this paper, we survey the literature to provide the most up-to-date snapshot of the frontiers of fairness in RL. We start by reviewing where fairness considerations can arise in RL, then discuss the various definitions of fairness in RL that have been put forth thus far. We continue to highlight the methodologies researchers used to implement fairness in single- and multi-agent RL systems before showcasing the distinct application domains that fair RL has been investigated in. Finally, we critically examine gaps in the literature, such as understanding fairness in the context of RLHF, that still need to be addressed in future work to truly operationalize fair RL in real-world systems.
Key facts. Cited by 9 papers in the map (data through 14 Oct 2026). Placed in RL for games and combinatorial optimization, one of 15 directions in Deep reinforcement learning methods. Builds on 29 of its 66 references that are in the map. First posted on arXiv 11 May 2024.
Builds on
29 of 66 references.
References · 29
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17 more
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- 2020Fairness in Learning-Based Sequential Decision Algorithms: A Surveycited by 35
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Built on by
Citing papers per year: 2024: 1; 2025: 5; 2026: 3.
9 papers.
- 2025Counterfactually Fair Reinforcement Learning via Sequential Data Preprocessingcited by 5
- 2025Intersectional Fairness in Reinforcement Learning with Large State and Constraint Spacescited by 5
- 2025Fairness Aware Reinforcement Learning via Proximal Policy Optimizationcited by 2
- 2026Fairness under uncertainty in sequential decisionscited by 2
- 2024Fair Resource Allocation in Weakly Coupled Markov Decision Processescited by 0
- 2025MAFE: Enabling Equitable Algorithm Design in Multi-Agent Multi-Stage Decision-Making Systemscited by 0
- 2025FairMarket-RL: LLM-Guided Fairness Shaping for Multi-Agent Reinforcement Learning in Peer-to-Peer Marketscited by 0
- 2026Boosted Distributional Reinforcement Learning: Analysis and Healthcare Applicationscited by 0
- 2026Price of Fairness in Short-Term and Long-Term Algorithmic Selectionscited by 0
- 2026Price of Fairness in Short-Term and Long-Term Algorithmic Selections7 May 2026
- 2026Fairness under uncertainty in sequential decisions23 Apr 2026
- 2026Boosted Distributional Reinforcement Learning: Analysis and Healthcare Applications6 Apr 2026
- 2025FairMarket-RL: LLM-Guided Fairness Shaping for Multi-Agent Reinforcement Learning in Peer-to-Peer Markets28 Jun 2025
- 2025MAFE: Enabling Equitable Algorithm Design in Multi-Agent Multi-Stage Decision-Making Systems25 Feb 2025
- 2025Intersectional Fairness in Reinforcement Learning with Large State and Constraint Spaces17 Feb 2025
- 2025Fairness Aware Reinforcement Learning via Proximal Policy Optimization6 Feb 2025
- 2025Counterfactually Fair Reinforcement Learning via Sequential Data Preprocessing10 Jan 2025
- 2024Fair Resource Allocation in Weakly Coupled Markov Decision Processes14 Nov 2024
Similar, not cited
Close in wording, no citation either way
- 2025Group Fairness in Multi-Task Reinforcement Learning
- 2024Striking a Balance in Fairness for Dynamic Systems Through Reinforcement Learning
- 2025PyCFRL: A Python library for counterfactually fair offline reinforcement learning via sequential data preprocessing
- 2023Achieving Fairness in Multi-Agent Markov Decision Processes Using Reinforcement Learning
- 2024Balancing the Scales: Reinforcement Learning for Fair Classification
- 2026FairTest: Search-Based Fairness Testing for Multi-Agent Reinforcement Learning Systems
- 2024What Hides behind Unfairness? Exploring Dynamics Fairness in Reinforcement Learning
- 2025Towards Reward Fairness in RLHF: From a Resource Allocation Perspective