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+# Governance — photon-mosaic
+
+## Overview
+The `photon-mosaic` organization is a collaboration between the [Neuroinformatics Unit (NIU)](https://neuroinformatics.dev/) and the [Allen Institute for Brain Science](https://alleninstitute.org/division/brain-science/), aimed at developing open, modular, and reproducible tools for multiphoton imaging analysis.  
+This governance document outlines how technical and strategic decisions are made within the organization.
+
+Our guiding principles are transparency, collaboration, and shared responsibility.
+
+---
+
+## Decision-Making Process
+
+### Consensus and Discussion
+Most technical and organizational decisions should be made by consensus among maintainers through open discussions on GitHub (Issues and Pull Requests) and Zulip. 
+All decisions should be documented and traceable.
+
+### Escalation
+If consensus cannot be reached, the issue is escalated to a joint steering group composed of representatives from NIU and the Allen Institute.  
+
+### Transparency
+All governance discussions and decisions should remain visible and accessible to contributors whenever possible.
+
+---
+
+## Roles and Responsibilities
+
+### Maintainers
+Maintainers are responsible for:
+- Reviewing and merging pull requests
+- Managing releases
+- Ensuring code quality and documentation standards
+- Coordinating across teams and institutions
+- Approving or proposing architectural changes
+
+Each participating institution designates at least one maintainer with merge rights.  
+Maintainers are expected to review each other’s work, particularly across institutional boundaries. Preferably at least one member of the Allen Institute and one of the NIU should be involved in the decision making process.
+
+### Contributors
+Contributors include anyone who:
+- Submits pull requests, issues, or documentation
+- Participates in code review or discussions
+- Proposes new features or improvements
+
+Contributors are expected to follow the [CONTRIBUTING.md](./CONTRIBUTING.md) guidelines and the project’s Code of Conduct.
+
+---
+
+## Communication Channels
+
+- Zulip for initial or non-technical enquires from users and contributors
+- GitHub Issues for bug reports, proposals, and technical discussions  
+- Meetings for regular updates between the maintainers and roadmap alignment
+
+---
+
+## Meetings
+
+- **Biweekly technical syncs** — review progress and coordinate development priorities  
+
+Meeting summaries are posted on [Zulip](https://neuroinformatics.zulipchat.com/#narrow/channel/500681-photon-mosaic/topic/Meeting.20Minutes/with/554330113).
+
+---
+
+## Code of Conduct
+
+All participants must adhere to the project’s [Code of Conduct](./CODE_OF_CONDUCT.md) to maintain a respectful, inclusive, and welcoming community.
+
+---
+
+## Contact
+
+- Lead maintainer: @lauraporta, l.porta@ucl.ac.uk
+