# A Policy Gradient Algorithm for Learning to Learn in Multiagent Reinforcement Learning

arXiv: https://arxiv.org/abs/2011.00382 · HTML: https://mlsanity.com/paper/2011.00382/

## Key facts

- Cited by 41 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 31 Oct 2020.

## Built on by (most cited first, 30 of 41)

- [Plan Better Amid Conservatism: Offline Multi-Agent Reinforcement Learning with Actor Rectification](https://mlsanity.com/paper/2111.11188/) (2021)
- [Model-Free Opponent Shaping](https://mlsanity.com/paper/2205.01447/) (2022)
- [Position: Theory of Mind Benchmarks are Broken for Large Language Models](https://mlsanity.com/paper/2412.19726/) (2024)
- [Model-Based Opponent Modeling](https://mlsanity.com/paper/2108.01843/) (2021)
- [Quantum Architecture Search via Continual Reinforcement Learning](https://mlsanity.com/paper/2112.05779/) (2021)
- [Influencing Long-Term Behavior in Multiagent Reinforcement Learning](https://mlsanity.com/paper/2203.03535/) (2022)
- [ROMAX: Certifiably Robust Deep Multiagent Reinforcement Learning via Convex Relaxation](https://mlsanity.com/paper/2109.06795/) (2021)
- [Continual Learning In Environments With Polynomial Mixing Times](https://mlsanity.com/paper/2112.07066/) (2021)
- [A Theoretical Understanding of Gradient Bias in Meta-Reinforcement Learning](https://mlsanity.com/paper/2112.15400/) (2021)
- [When Meta-Learning Meets Online and Continual Learning: A Survey](https://mlsanity.com/paper/2311.05241/) (2023)
- [Scaling Opponent Shaping to High Dimensional Games](https://mlsanity.com/paper/2312.12568/) (2023)
- [LOQA: Learning with Opponent Q-Learning Awareness](https://mlsanity.com/paper/2405.01035/) (2024)
- [Fast Peer Adaptation with Context-aware Exploration](https://mlsanity.com/paper/2402.02468/) (2024)
- [Enabling Realtime Reinforcement Learning at Scale with Staggered Asynchronous Inference](https://mlsanity.com/paper/2412.14355/) (2024)
- [Meta-Value Learning: a General Framework for Learning with Learning Awareness](https://mlsanity.com/paper/2307.08863/) (2023)
- [Dealing with Non-Stationarity in MARL via Trust-Region Decomposition](https://mlsanity.com/paper/2102.10616/) (2021)
- [Game-Theoretical Perspectives on Active Equilibria: A Preferred Solution Concept over Nash Equilibria](https://mlsanity.com/paper/2210.16175/) (2022)
- [(Ir)rationality in AI: State of the Art, Research Challenges and Open Questions](https://mlsanity.com/paper/2311.17165/) (2023)
- [Multi-agent cooperation through learning-aware policy gradients](https://mlsanity.com/paper/2410.18636/) (2024)
- [Graph Neural Networks for Decentralized Multi-Agent Perimeter Defense](https://mlsanity.com/paper/2301.09689/) (2023)
- [MultiPrompter: Cooperative Prompt Optimization with Multi-Agent Reinforcement Learning](https://mlsanity.com/paper/2310.16730/) (2023)
- [Reciprocal Reward Influence Encourages Cooperation From Self-Interested Agents](https://mlsanity.com/paper/2406.01641/) (2024)
- [Role Play: Learning Adaptive Role-Specific Strategies in Multi-Agent Interactions](https://mlsanity.com/paper/2411.01166/) (2024)
- [Beyond Sliding Windows: Learning to Manage Memory in Non-Markovian Environments](https://mlsanity.com/paper/2512.19154/) (2025)
- [Neural Auto-Curricula](https://mlsanity.com/paper/2106.02745/) (2021)
- [Offline Equilibrium Finding](https://mlsanity.com/paper/2207.05285/) (2022)
- [Decision-making with Speculative Opponent Models](https://mlsanity.com/paper/2211.11940/) (2022)
- [Analysing the Sample Complexity of Opponent Shaping](https://mlsanity.com/paper/2402.05782/) (2024)
- [Robust and Diverse Multi-Agent Learning via Rational Policy Gradient](https://mlsanity.com/paper/2511.09535/) (2025)
- [The Effectiveness of Approximate Regularized Replay for Efficient Supervised Fine-Tuning of Large Language Models](https://mlsanity.com/paper/2512.22337/) (2025)

## Abstract (arXiv)

A fundamental challenge in multiagent reinforcement learning is to learn beneficial behaviors in a shared environment with other simultaneously learning agents. In particular, each agent perceives the environment as effectively non-stationary due to the changing policies of other agents. Moreover, each agent is itself constantly learning, leading to natural non-stationarity in the distribution of experiences encountered. In this paper, we propose a novel meta-multiagent policy gradient theorem that directly accounts for the non-stationary policy dynamics inherent to multiagent learning settings. This is achieved by modeling our gradient updates to consider both an agent's own non-stationary policy dynamics and the non-stationary policy dynamics of other agents in the environment. We show that our theoretically grounded approach provides a general solution to the multiagent learning problem, which inherently comprises all key aspects of previous state of the art approaches on this topic. We test our method on a diverse suite of multiagent benchmarks and demonstrate a more efficient ability to adapt to new agents as they learn than baseline methods across the full spectrum of mixed incentive, competitive, and cooperative domains.
