diff --git a/src/languages/definitions/cedar/cedar.ts b/src/languages/definitions/cedar/cedar.ts
new file mode 100644
index 0000000000..c9729bc9a9
--- /dev/null
+++ b/src/languages/definitions/cedar/cedar.ts
@@ -0,0 +1,161 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import type { languages } from '../../../editor';
+
+export const conf: languages.LanguageConfiguration = {
+	comments: {
+		lineComment: '//'
+	},
+	brackets: [
+		['{', '}'],
+		['[', ']'],
+		['(', ')']
+	],
+	autoClosingPairs: [
+		{ open: '{', close: '}' },
+		{ open: '[', close: ']' },
+		{ open: '(', close: ')' },
+		{ open: '"', close: '"', notIn: ['string'] }
+	],
+	surroundingPairs: [
+		{ open: '{', close: '}' },
+		{ open: '[', close: ']' },
+		{ open: '(', close: ')' },
+		{ open: '"', close: '"' }
+	]
+};
+
+export const language = <languages.IMonarchLanguage>{
+	defaultToken: '',
+	tokenPostfix: '.cedar',
+
+	// sections + keywords from TextMate grammar
+	keywords: ['permit', 'forbid', 'when', 'unless', 'in', 'has', 'like', 'if', 'then', 'else', 'is'],
+
+	// principal, action, resource, context
+	constants: ['principal', 'action', 'resource', 'context'],
+
+	// true, false
+	booleans: ['true', 'false'],
+
+	// extension functions
+	functions: ['ip', 'decimal', 'datetime', 'duration'],
+
+	// all methods (methods + ipmethods + decimalmethods + datetimemethods + durationmethods)
+	methods: [
+		'contains',
+		'containsAll',
+		'containsAny',
+		'isEmpty',
+		'getTag',
+		'hasTag',
+		'isIpv4',
+		'isIpv6',
+		'isLoopback',
+		'isMulticast',
+		'isInRange',
+		'lessThan',
+		'lessThanOrEqual',
+		'greaterThan',
+		'greaterThanOrEqual',
+		'offset',
+		'durationSince',
+		'toDate',
+		'toTime',
+		'toMilliseconds',
+		'toSeconds',
+		'toMinutes',
+		'toHours',
+		'toDays'
+	],
+
+	symbols: /[=!<>|&+\-*\/]+/,
+
+	tokenizer: {
+		root: [
+			// comments
+			[/\/\/.*$/, 'comment'],
+
+			// annotations: @name(
+			[/@[_a-zA-Z][_a-zA-Z0-9]*(?=\()/, 'annotation'],
+
+			// ?principal, ?resource
+			[/\?(?:principal|resource)\b/, 'variable'],
+
+			// method calls: .methodName(
+			[
+				/\.([a-zA-Z][a-zA-Z0-9]*)(?=\()/,
+				{
+					cases: {
+						'$1@methods': 'keyword.function',
+						'@default': 'identifier'
+					}
+				}
+			],
+
+			// extension functions: ip(, decimal(, datetime(, duration(
+			[
+				/[a-z][a-zA-Z0-9]*(?=\()/,
+				{
+					cases: {
+						'@functions': 'keyword.function',
+						'@default': 'identifier'
+					}
+				}
+			],
+
+			// entity type references with :: before a string: Namespace::Type::
+			[
+				/[_a-zA-Z][_a-zA-Z0-9]*(?:::[_a-zA-Z][_a-zA-Z0-9]*)*(?=::(?="))/,
+				'type.identifier'
+			],
+
+			// namespaced types: Namespace::Type
+			[
+				/[_a-zA-Z][_a-zA-Z0-9]*(?:::[_a-zA-Z][_a-zA-Z0-9]*)+/,
+				'type.identifier'
+			],
+
+			// identifiers, keywords, constants, booleans
+			[
+				/[_a-zA-Z][_a-zA-Z0-9]*/,
+				{
+					cases: {
+						'@keywords': 'keyword',
+						'@constants': 'variable',
+						'@booleans': 'constant',
+						'@default': 'identifier'
+					}
+				}
+			],
+
+			// integers
+			[/[1-9][0-9]*|0/, 'number'],
+
+			// whitespace
+			[/[ \t\r\n]+/, ''],
+
+			// brackets
+			[/[{}()\[\]]/, '@brackets'],
+
+			// operators
+			[/@symbols/, 'operator'],
+
+			// strings
+			[/"([^"\\]|\\.)*$/, 'string.invalid'],
+			[/"/, { token: 'string.quote', bracket: '@open', next: '@string' }],
+
+			// delimiters
+			[/[;,.]/, 'delimiter']
+		],
+
+		string: [
+			[/[^\\"]+/, 'string'],
+			[/\\./, 'string.escape'],
+			[/"/, { token: 'string.quote', bracket: '@close', next: '@pop' }]
+		]
+	}
+};
diff --git a/src/languages/definitions/cedar/register.ts b/src/languages/definitions/cedar/register.ts
new file mode 100644
index 0000000000..a01cd28efd
--- /dev/null
+++ b/src/languages/definitions/cedar/register.ts
@@ -0,0 +1,13 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { registerLanguage } from '../_.contribution';
+
+registerLanguage({
+	id: 'cedar',
+	extensions: ['.cedar'],
+	aliases: ['Cedar', 'cedar'],
+	loader: () => import('./cedar')
+});
diff --git a/src/languages/definitions/cedarschema/cedarschema.ts b/src/languages/definitions/cedarschema/cedarschema.ts
new file mode 100644
index 0000000000..85685c12ff
--- /dev/null
+++ b/src/languages/definitions/cedarschema/cedarschema.ts
@@ -0,0 +1,103 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import type { languages } from '../../../editor';
+
+export const conf: languages.LanguageConfiguration = {
+	comments: {
+		lineComment: '//'
+	},
+	brackets: [
+		['{', '}'],
+		['[', ']'],
+		['(', ')']
+	],
+	autoClosingPairs: [
+		{ open: '{', close: '}' },
+		{ open: '[', close: ']' },
+		{ open: '(', close: ')' },
+		{ open: '"', close: '"', notIn: ['string'] }
+	],
+	surroundingPairs: [
+		{ open: '{', close: '}' },
+		{ open: '[', close: ']' },
+		{ open: '(', close: ')' },
+		{ open: '"', close: '"' }
+	]
+};
+
+export const language = <languages.IMonarchLanguage>{
+	defaultToken: '',
+	tokenPostfix: '.cedarschema',
+
+	keywords: ['namespace', 'type', 'entity', 'action', 'appliesTo', 'in', 'enum', 'tags'],
+
+	typeKeywords: ['Long', 'String', 'Bool', 'Set', 'Record', 'Entity', 'Extension'],
+
+	symbols: /[=:?<>]+/,
+
+	tokenizer: {
+		root: [
+			// comments
+			[/\/\/.*$/, 'comment'],
+
+			// namespace path (e.g. My::Namespace::Path)
+			[
+				/[A-Z_a-z][A-Za-z0-9_]*(?:::[A-Z_a-z][A-Za-z0-9_]*)+/,
+				'entity.name.namespace'
+			],
+
+			// properties (identifier followed by optional ? then : but not ::)
+			[/[_a-zA-Z][_a-zA-Z0-9]*(?=\??\s*:(?!:))/, 'variable.property'],
+
+			// identifiers and keywords
+			[
+				/[a-z_][A-Za-z0-9_]*/,
+				{
+					cases: {
+						'@keywords': 'keyword',
+						'@default': 'identifier'
+					}
+				}
+			],
+
+			// type identifiers (capitalized)
+			[
+				/[A-Z][A-Za-z0-9_]*/,
+				{
+					cases: {
+						'@typeKeywords': 'type.identifier',
+						'@default': 'type.identifier'
+					}
+				}
+			],
+
+			// whitespace
+			[/[ \t\r\n]+/, ''],
+
+			// brackets
+			[/[{}()\[\]]/, '@brackets'],
+
+			// operators / symbols
+			[/@symbols/, 'operator'],
+
+			// optional marker
+			[/\?/, 'operator'],
+
+			// strings
+			[/"([^"\\]|\\.)*$/, 'string.invalid'],
+			[/"/, { token: 'string.quote', bracket: '@open', next: '@string' }],
+
+			// delimiter
+			[/[;,.]/, 'delimiter']
+		],
+
+		string: [
+			[/[^\\"]+/, 'string'],
+			[/\\./, 'string.escape'],
+			[/"/, { token: 'string.quote', bracket: '@close', next: '@pop' }]
+		]
+	}
+};
diff --git a/src/languages/definitions/cedarschema/register.ts b/src/languages/definitions/cedarschema/register.ts
new file mode 100644
index 0000000000..a84d2e9f41
--- /dev/null
+++ b/src/languages/definitions/cedarschema/register.ts
@@ -0,0 +1,13 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { registerLanguage } from '../_.contribution';
+
+registerLanguage({
+	id: 'cedarschema',
+	extensions: ['.cedarschema'],
+	aliases: ['Cedar Schema', 'cedarschema'],
+	loader: () => import('./cedarschema')
+});
diff --git a/src/languages/definitions/register.all.ts b/src/languages/definitions/register.all.ts
index ff00612225..6fb3523c2d 100644
--- a/src/languages/definitions/register.all.ts
+++ b/src/languages/definitions/register.all.ts
@@ -9,6 +9,8 @@ import './azcli/register';
 import './bat/register';
 import './bicep/register';
 import './cameligo/register';
+import './cedar/register';
+import './cedarschema/register';
 import './clojure/register';
 import './coffee/register';
 import './cpp/register';
diff --git a/website/src/website/data/home-samples/sample.cedar.txt b/website/src/website/data/home-samples/sample.cedar.txt
new file mode 100644
index 0000000000..e7961e2ba6
--- /dev/null
+++ b/website/src/website/data/home-samples/sample.cedar.txt
@@ -0,0 +1,19 @@
+@id("policy1")
+permit (
+    principal in Group::"admins",
+    action == Action::"viewDocument",
+    resource
+)
+when {
+    resource has owner &&
+    resource.owner == principal
+};
+
+forbid (
+    principal,
+    action == Action::"deleteDocument",
+    resource
+)
+unless {
+    principal in Group::"superadmins"
+};
diff --git a/website/src/website/data/home-samples/sample.cedarschema.txt b/website/src/website/data/home-samples/sample.cedarschema.txt
new file mode 100644
index 0000000000..706f9a54e1
--- /dev/null
+++ b/website/src/website/data/home-samples/sample.cedarschema.txt
@@ -0,0 +1,23 @@
+namespace MyApp {
+    entity User in [Group] {
+        name: String,
+        email?: String,
+    };
+
+    entity Group in [Group];
+
+    entity Document {
+        owner: User,
+        isPublic: Bool,
+    };
+
+    action viewDocument appliesTo {
+        principal: [User],
+        resource: [Document],
+    };
+
+    action deleteDocument appliesTo {
+        principal: [User],
+        resource: [Document],
+    };
+}