--- layout: docs page_title: ACL Guides sidebar_title: 'Access Control (ACLs)' sidebar_current: docs-acl-index description: >- Consul provides an optional Access Control List (ACL) system which can be used to control access to data and APIs. Select the following guide for your use case. --- # ACL Documentation and Guides Consul uses Access Control Lists (ACLs) to secure the UI, API, CLI, service communications, and agent communications. At the core, ACLs operate by grouping rules into policies, then associating one or more policies with a token. The following documentation and guides will help you understand and implement ACLs. ## ACL Documentation ### ACL System Consul provides an optional Access Control List (ACL) system which can be used to control access to data and APIs. The ACL system is a Capability-based system that relies on tokens which can have fine grained rules applied to them. The [ACL System documentation](/docs/acl/acl-system.html) details the functionality of Consul ACLs. ### ACL Rules A core part of the ACL system is the rule language, which is used to describe the policy that must be enforced. Read the ACL rules [documentation](/docs/acl/acl-rules.html) to learn about rule specifications. ### ACL Auth Methods An auth method is a component in Consul that performs authentication against a trusted external party to authorize the creation of an ACL tokens usable within the local datacenter. Read the ACL auth method [documentation](/docs/acl/acl-auth-methods.html) to learn more about how they work and why you may want to use them. ### ACL Legacy System The ACL system in Consul 1.3.1 and older is now called legacy. For information on bootstrapping the legacy system, ACL rules, and a general ACL system overview, read the legacy [documentation](/docs/acl/acl-legacy.html). ### ACL Migration [The migration documentation](/docs/acl/acl-migrate-tokens.html) details how to upgrade existing legacy tokens after upgrading to 1.4.0. It will briefly describe what changed, and then walk through the high-level migration process options, finally giving some specific examples of migration strategies. The new ACL system has improvements for the security and management of ACL tokens and policies. ## Learn ACL Guide ~> Note: the following guide is located on HashiCorp Learn. By selecting it, you will be directed to a new site. ### Securing Consul with ACLs In this guide, you will learn how to secure the UI, API, CLI, service communications, and agent communications with ACLs. When securing your cluster you should configure the ACLs first. The ACL documentation introduces basic concepts and syntax for the ACL system, and we recommend that you read it before you begin [this guide](https://learn.hashicorp.com/consul/security-networking/production-acls).