diff --git a/Gulpfile.ts b/Gulpfile.ts
index 03046789fe1de..d856254296eb7 100644
--- a/Gulpfile.ts
+++ b/Gulpfile.ts
@@ -131,6 +131,7 @@ const es2017LibrarySource = [
     "es2017.object.d.ts",
     "es2017.sharedmemory.d.ts",
     "es2017.string.d.ts",
+    "es2017.intl.d.ts",
 ];
 
 const es2017LibrarySourceMap = es2017LibrarySource.map(function(source) {
diff --git a/Jakefile.js b/Jakefile.js
index 807546d59f87e..577ade2ef697e 100644
--- a/Jakefile.js
+++ b/Jakefile.js
@@ -172,7 +172,8 @@ var es2016LibrarySourceMap = es2016LibrarySource.map(function (source) {
 var es2017LibrarySource = [
     "es2017.object.d.ts",
     "es2017.sharedmemory.d.ts",
-    "es2017.string.d.ts"
+    "es2017.string.d.ts",
+    "es2017.intl.d.ts"
 ];
 
 var es2017LibrarySourceMap = es2017LibrarySource.map(function (source) {
diff --git a/lib/lib.es2017.d.ts b/lib/lib.es2017.d.ts
index a0d3a0aff2826..64ebe6068478c 100644
--- a/lib/lib.es2017.d.ts
+++ b/lib/lib.es2017.d.ts
@@ -21,4 +21,5 @@ and limitations under the License.
 /// <reference path="lib.es2016.d.ts" />
 /// <reference path="lib.es2017.object.d.ts" />
 /// <reference path="lib.es2017.sharedmemory.d.ts" />
-/// <reference path="lib.es2017.string.d.ts" />
\ No newline at end of file
+/// <reference path="lib.es2017.string.d.ts" />
+/// <reference path="lib.es2017.intl.d.ts" />
\ No newline at end of file
diff --git a/lib/lib.es2017.full.d.ts b/lib/lib.es2017.full.d.ts
index d70049b130983..91bee6e9d568b 100644
--- a/lib/lib.es2017.full.d.ts
+++ b/lib/lib.es2017.full.d.ts
@@ -22,6 +22,7 @@ and limitations under the License.
 /// <reference path="lib.es2017.object.d.ts" />
 /// <reference path="lib.es2017.sharedmemory.d.ts" />
 /// <reference path="lib.es2017.string.d.ts" />
+/// <reference path="lib.es2017.intl.d.ts" />
 
 declare type PropertyKey = string | number | symbol;
 
diff --git a/lib/tsc.js b/lib/tsc.js
index 1d92d339b9d4f..4c846c034f834 100644
--- a/lib/tsc.js
+++ b/lib/tsc.js
@@ -56880,6 +56880,7 @@ var ts;
                     "es2017.object": "lib.es2017.object.d.ts",
                     "es2017.sharedmemory": "lib.es2017.sharedmemory.d.ts",
                     "es2017.string": "lib.es2017.string.d.ts",
+                    "es2017.intl": "lib.es2017.intl.d.ts",
                     "esnext.asynciterable": "lib.esnext.asynciterable.d.ts",
                 }),
             },
diff --git a/lib/tsserver.js b/lib/tsserver.js
index ae6c3c8dc0791..0e99abde9da5d 100644
--- a/lib/tsserver.js
+++ b/lib/tsserver.js
@@ -56898,6 +56898,7 @@ var ts;
                     "es2017.object": "lib.es2017.object.d.ts",
                     "es2017.sharedmemory": "lib.es2017.sharedmemory.d.ts",
                     "es2017.string": "lib.es2017.string.d.ts",
+                    "es2017.intl": "lib.es2017.intl.d.ts",
                     "esnext.asynciterable": "lib.esnext.asynciterable.d.ts",
                 }),
             },
diff --git a/lib/tsserverlibrary.js b/lib/tsserverlibrary.js
index e23edda9295b0..128438ce66a3f 100644
--- a/lib/tsserverlibrary.js
+++ b/lib/tsserverlibrary.js
@@ -6079,6 +6079,7 @@ var ts;
                     "es2017.object": "lib.es2017.object.d.ts",
                     "es2017.sharedmemory": "lib.es2017.sharedmemory.d.ts",
                     "es2017.string": "lib.es2017.string.d.ts",
+                    "es2017.intl": "lib.es2017.intl.d.ts",
                     "esnext.asynciterable": "lib.esnext.asynciterable.d.ts",
                 }),
             },
diff --git a/lib/typescript.js b/lib/typescript.js
index a73895f4f74e7..9f28644b4e5c3 100644
--- a/lib/typescript.js
+++ b/lib/typescript.js
@@ -69276,6 +69276,7 @@ var ts;
                     "es2017.object": "lib.es2017.object.d.ts",
                     "es2017.sharedmemory": "lib.es2017.sharedmemory.d.ts",
                     "es2017.string": "lib.es2017.string.d.ts",
+                    "es2017.intl": "lib.es2017.intl.d.ts",
                     "esnext.asynciterable": "lib.esnext.asynciterable.d.ts",
                 }),
             },
diff --git a/lib/typescriptServices.js b/lib/typescriptServices.js
index a73895f4f74e7..9f28644b4e5c3 100644
--- a/lib/typescriptServices.js
+++ b/lib/typescriptServices.js
@@ -69276,6 +69276,7 @@ var ts;
                     "es2017.object": "lib.es2017.object.d.ts",
                     "es2017.sharedmemory": "lib.es2017.sharedmemory.d.ts",
                     "es2017.string": "lib.es2017.string.d.ts",
+                    "es2017.intl": "lib.es2017.intl.d.ts",
                     "esnext.asynciterable": "lib.esnext.asynciterable.d.ts",
                 }),
             },
diff --git a/lib/typingsInstaller.js b/lib/typingsInstaller.js
index 4efda1e469e42..554dc3bcacaf5 100644
--- a/lib/typingsInstaller.js
+++ b/lib/typingsInstaller.js
@@ -6071,6 +6071,7 @@ var ts;
                     "es2017.object": "lib.es2017.object.d.ts",
                     "es2017.sharedmemory": "lib.es2017.sharedmemory.d.ts",
                     "es2017.string": "lib.es2017.string.d.ts",
+                    "es2017.intl": "lib.es2017.intl.d.ts",
                     "esnext.asynciterable": "lib.esnext.asynciterable.d.ts",
                 }),
             },
diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 9494098c072f3..88687357115c1 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -139,6 +139,7 @@ namespace ts {
                     "es2017.object": "lib.es2017.object.d.ts",
                     "es2017.sharedmemory": "lib.es2017.sharedmemory.d.ts",
                     "es2017.string": "lib.es2017.string.d.ts",
+                    "es2017.intl": "lib.es2017.intl.d.ts",
                     "esnext.asynciterable": "lib.esnext.asynciterable.d.ts",
                 }),
             },
@@ -1704,4 +1705,4 @@ namespace ts {
     function caseInsensitiveKeyMapper(key: string) {
         return key.toLowerCase();
     }
-}
\ No newline at end of file
+}
diff --git a/src/harness/unittests/commandLineParsing.ts b/src/harness/unittests/commandLineParsing.ts
index 61b96d8955346..19ccc919d4c09 100644
--- a/src/harness/unittests/commandLineParsing.ts
+++ b/src/harness/unittests/commandLineParsing.ts
@@ -60,7 +60,7 @@ namespace ts {
             assertParseResult(["--lib", "es5,invalidOption", "0.ts"],
                 {
                     errors: [{
-                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'esnext.asynciterable'.",
+                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'es2017.intl', 'esnext.asynciterable'.",
                         category: ts.Diagnostics.Argument_for_0_option_must_be_Colon_1.category,
                         code: ts.Diagnostics.Argument_for_0_option_must_be_Colon_1.code,
 
@@ -263,7 +263,7 @@ namespace ts {
             assertParseResult(["--lib", "es5,", "es7", "0.ts"],
                 {
                     errors: [{
-                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'esnext.asynciterable'.",
+                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'es2017.intl', 'esnext.asynciterable'.",
                         category: ts.Diagnostics.Argument_for_0_option_must_be_Colon_1.category,
                         code: ts.Diagnostics.Argument_for_0_option_must_be_Colon_1.code,
 
@@ -283,7 +283,7 @@ namespace ts {
             assertParseResult(["--lib", "es5, ", "es7", "0.ts"],
                 {
                     errors: [{
-                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'esnext.asynciterable'.",
+                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'es2017.intl', 'esnext.asynciterable'.",
                         category: ts.Diagnostics.Argument_for_0_option_must_be_Colon_1.category,
                         code: ts.Diagnostics.Argument_for_0_option_must_be_Colon_1.code,
 
diff --git a/src/harness/unittests/convertCompilerOptionsFromJson.ts b/src/harness/unittests/convertCompilerOptionsFromJson.ts
index 0409ee19e66d0..3aa1a4c9b8e6a 100644
--- a/src/harness/unittests/convertCompilerOptionsFromJson.ts
+++ b/src/harness/unittests/convertCompilerOptionsFromJson.ts
@@ -233,7 +233,7 @@ namespace ts {
                         file: undefined,
                         start: 0,
                         length: 0,
-                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'esnext.asynciterable'.",
+                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'es2017.intl', 'esnext.asynciterable'.",
                         code: Diagnostics.Argument_for_0_option_must_be_Colon_1.code,
                         category: Diagnostics.Argument_for_0_option_must_be_Colon_1.category
                     }]
@@ -264,7 +264,7 @@ namespace ts {
                         file: undefined,
                         start: 0,
                         length: 0,
-                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'esnext.asynciterable'.",
+                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'es2017.intl', 'esnext.asynciterable'.",
                         code: Diagnostics.Argument_for_0_option_must_be_Colon_1.code,
                         category: Diagnostics.Argument_for_0_option_must_be_Colon_1.category
                     }]
@@ -295,7 +295,7 @@ namespace ts {
                         file: undefined,
                         start: 0,
                         length: 0,
-                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'esnext.asynciterable'.",
+                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'es2017.intl', 'esnext.asynciterable'.",
                         code: Diagnostics.Argument_for_0_option_must_be_Colon_1.code,
                         category: Diagnostics.Argument_for_0_option_must_be_Colon_1.category
                     }]
@@ -326,7 +326,7 @@ namespace ts {
                         file: undefined,
                         start: 0,
                         length: 0,
-                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'esnext.asynciterable'.",
+                        messageText: "Argument for '--lib' option must be: 'es5', 'es6', 'es2015', 'es7', 'es2016', 'es2017', 'esnext', 'dom', 'dom.iterable', 'webworker', 'scripthost', 'es2015.core', 'es2015.collection', 'es2015.generator', 'es2015.iterable', 'es2015.promise', 'es2015.proxy', 'es2015.reflect', 'es2015.symbol', 'es2015.symbol.wellknown', 'es2016.array.include', 'es2017.object', 'es2017.sharedmemory', 'es2017.string', 'es2017.intl', 'esnext.asynciterable'.",
                         code: Diagnostics.Argument_for_0_option_must_be_Colon_1.code,
                         category: Diagnostics.Argument_for_0_option_must_be_Colon_1.category
                     }]
diff --git a/src/lib/es2017.d.ts b/src/lib/es2017.d.ts
index 7b8c7cbb7d5be..80282355a45b3 100644
--- a/src/lib/es2017.d.ts
+++ b/src/lib/es2017.d.ts
@@ -1,4 +1,5 @@
 /// <reference path="lib.es2016.d.ts" />
 /// <reference path="lib.es2017.object.d.ts" />
 /// <reference path="lib.es2017.sharedmemory.d.ts" />
-/// <reference path="lib.es2017.string.d.ts" />
\ No newline at end of file
+/// <reference path="lib.es2017.string.d.ts" />
+/// <reference path="lib.es2017.intl.d.ts" />
diff --git a/src/lib/es2017.intl.d.ts b/src/lib/es2017.intl.d.ts
new file mode 100644
index 0000000000000..b878353019082
--- /dev/null
+++ b/src/lib/es2017.intl.d.ts
@@ -0,0 +1,10 @@
+type DateTimeFormatPartTypes = "day" | "dayPeriod" | "era" | "hour" | "literal" | "minute" | "month" | "second" | "timeZoneName" | "weekday" | "year";
+
+interface DateTimeFormatPart {
+    type: DateTimeFormatPartTypes;
+    value: string;
+}
+
+interface DateTimeFormat {
+    formatToParts(date?: Date | number): DateTimeFormatPart[];
+}