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+# Access Control
+
+OpenCVE uses a **role-based access control** system with two levels: **organization** and **project**.
+
+This model helps teams collaborate safely: you control who can manage the organization, who can create projects, and who can work on CVEs inside each project, without giving everyone full access to everything.
+
+## Why use organization and project roles?
+
+Roles let you match access to how your team actually works:
+
+- delegate organization administration (members, API tokens, projects) without sharing full owner rights,
+- give each team access only to the projects they need,
+- offer read-only visibility on some projects while allowing CVE triage on others.
+
+OpenCVE separates this into:
+
+- **Organization roles**: who can manage the workspace (members, tokens, projects, settings),
+- **Project roles**: who can view or operate on CVEs inside a given project,
+
+## How it works
+
+```mermaid
+flowchart TB
+    user[User]
+    orgMembership[Organization membership]
+    projectMembership[Project membership optional]
+    orgPerms[Organization permissions]
+    projectPerms[Project permissions]
+
+    user --> orgMembership
+    orgMembership --> orgPerms
+    orgMembership --> projectMembership
+    projectMembership --> projectPerms
+    orgMembership -->|"Owner or Admin"| implicitAdmin[Implicit Project Admin on all projects]
+    implicitAdmin --> projectPerms
+```
+
+Key rules:
+
+1. A user must belong to the organization (invitation accepted, not pending) before they can be added to a project.
+2. **Organization Members** only see and access projects they are explicitly assigned to.
+3. **Organization Owners and Admins** have **Project Admin** rights on every project in the organization, even if they are not listed on the project members page.
+4. Pending invitations (`not yet joined`) have no access until the user accepts.
+
+!!! info "API tokens are separate"
+    Organization API tokens (REST API v2) are not user ACL proxies. They authenticate as the organization itself with read/write scope. User roles described in this guide apply to the web UI and user-based flows.
+
+## Organization roles
+
+Each user has one organization role per organization:
+
+| Role | Summary |
+|------|---------|
+| **Owner** | Full control over the organization, including deletion and audit logs. |
+| **Admin** | Manage members (Members only), tokens, and projects. Cannot edit organization settings or delete the organization. |
+| **Member** | Access the organization and projects they are assigned to. No organization administration. |
+
+### Organization permissions
+
+| Permission | Owner | Admin | Member |
+|------------|:-----:|:-----:|:------:|
+| Access the organization | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Edit organization settings | <input type="checkbox" checked disabled> | <input type="checkbox" disabled> | <input type="checkbox" disabled> |
+| Delete the organization | <input type="checkbox" checked disabled> | <input type="checkbox" disabled> | <input type="checkbox" disabled> |
+| View & manage members | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" disabled> |
+| Manage API tokens | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" disabled> |
+| View audit logs | <input type="checkbox" checked disabled> | <input type="checkbox" disabled> | <input type="checkbox" disabled> |
+| Create projects | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" disabled> |
+| Delete projects | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" disabled> |
+
+Member management details:
+
+- **Owners** can invite, change roles, and remove any member. Only Owners can assign the Owner or Admin role.
+- **Admins** can invite and manage Members only. They cannot change or remove Owners or other Admins.
+- **Members** cannot manage organization members.
+
+### Manage organization members
+
+Organization members are managed from the organization settings.
+
+![Organization members](../images/guides/access_control/organization-members.png){.center style="width:100%"}
+
+## Project roles
+
+Project roles apply to **organization Members** who have been added to a project.
+
+Organization **Owners** and **Admins** do not need a project membership: they already have **Project Admin** rights on all projects (see below).
+
+| Role | Summary |
+|------|---------|
+| **Viewer** | Read-only access to project data (CVEs, reports, automations, notifications, subscriptions). |
+| **Contributor** | Viewer + operational CVE work (assign, status, comments). |
+| **Project Admin** | Contributor + project management (settings, members, subscriptions, automations, notifications). |
+
+### Project permissions
+
+| Permission | Viewer | Contributor | Project Admin | Org Owner / Admin |
+|------------|:------:|:-----------:|:-------------:|:-----------------:|
+| View project & CVEs | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Export CVEs | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| View reports | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| View automations & notifications | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| View subscriptions | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| View project members | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Assign CVEs | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Update CVE status | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Comment on CVEs | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Edit project settings | <input type="checkbox" disabled> | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Manage project members | <input type="checkbox" disabled> | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Manage subscriptions | <input type="checkbox" disabled> | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Manage automations | <input type="checkbox" disabled> | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+| Manage notifications | <input type="checkbox" disabled> | <input type="checkbox" disabled> | <input type="checkbox" checked disabled> | <input type="checkbox" checked disabled> |
+
+### Implicit access for Owners and Admins
+
+Organization **Owners** and **Admins** automatically receive **Project Admin** permissions on all projects in the organization.
+
+They see every project in the navigation and dashboards, and can manage any project without being listed on the project members page.
+
+This avoids maintaining duplicate memberships for people who already administer the organization.
+
+### Organization Members and project access
+
+**Organization Members** only access projects where they have an explicit project membership.
+
+If a Member is not assigned to a project:
+
+- the project does not appear in their project list,
+- they cannot open the project or its CVEs,
+- they cannot be assigned to CVEs in that project.
+
+To grant access, a **Project Admin** (or an organization Owner/Admin) must add them from the project members page.
+
+![Project members](../images/guides/access_control/project-members.png){.center style="width:100%"}
+
+## Typical setups
+
+| Scenario | Suggested setup |
+|----------|-----------------|
+| Small team, one owner | Owner manages everything; add Members as **Contributors** on relevant projects. |
+| Delegated administration | Promote trusted users to **Admin**; keep **Owner** for billing-level control and audit logs. |
+| Read-only stakeholders | Add as organization **Member**, assign **Viewer** on selected projects. |
+| MSSP per-client projects | **Admin** or **Owner** creates projects; client contacts get **Viewer** or **Contributor** on their project only. |
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diff --git a/mkdocs.yml b/mkdocs.yml
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+++ b/mkdocs.yml
@@ -42,6 +42,7 @@ nav:
       - Knowledge Base (KB): 'concepts/kb.md'
       - Notifications: 'concepts/notifications.md'
   - Guides:
+      - Access Control: 'guides/access_control.md'
       - Advanced Search: 'guides/advanced_search.md'
       - Automations: 'guides/automations.md'
       - Dashboards: 'guides/dashboards.md'