diff --git a/src/compiler/moduleNameResolver.ts b/src/compiler/moduleNameResolver.ts
index ca702173e79..4ebdc59e6dd 100644
--- a/src/compiler/moduleNameResolver.ts
+++ b/src/compiler/moduleNameResolver.ts
@@ -95,7 +95,7 @@ namespace ts {
             currentDirectory = host.getCurrentDirectory();
         }
 
-        return currentDirectory && getDefaultTypeRoots(currentDirectory, host);
+        return currentDirectory !== undefined && getDefaultTypeRoots(currentDirectory, host);
     }
 
     /**
@@ -675,23 +675,33 @@ namespace ts {
 
     /* @internal */
     export function loadModuleFromNodeModules(moduleName: string, directory: string, failedLookupLocations: string[], state: ModuleResolutionState, checkOneLevel: boolean): string {
+        return loadModuleFromNodeModulesWorker(moduleName, directory, failedLookupLocations, state, checkOneLevel, /*typesOnly*/ false);
+    }
+
+    function loadModuleFromNodeModulesAtTypes(moduleName: string, directory: string, failedLookupLocations: string[], state: ModuleResolutionState): string {
+        return loadModuleFromNodeModulesWorker(moduleName, directory, failedLookupLocations, state, /*checkOneLevel*/ false, /*typesOnly*/ true);
+    }
+
+    function loadModuleFromNodeModulesWorker(moduleName: string, directory: string, failedLookupLocations: string[], state: ModuleResolutionState, checkOneLevel: boolean, typesOnly: boolean): string {
         directory = normalizeSlashes(directory);
         while (true) {
             const baseName = getBaseFileName(directory);
             if (baseName !== "node_modules") {
-                // Try to load source from the package
-                const packageResult = loadModuleFromNodeModulesFolder(moduleName, directory, failedLookupLocations, state);
-                if (packageResult && hasTypeScriptFileExtension(packageResult)) {
-                    // Always prefer a TypeScript (.ts, .tsx, .d.ts) file shipped with the package
-                    return packageResult;
-                }
-                else {
-                    // Else prefer a types package over non-TypeScript results (e.g. JavaScript files)
-                    const typesResult = loadModuleFromNodeModulesFolder(combinePaths("@types", moduleName), directory, failedLookupLocations, state);
-                    if (typesResult || packageResult) {
-                        return typesResult || packageResult;
+                let packageResult: string | undefined;
+                if (!typesOnly) {
+                    // Try to load source from the package
+                    packageResult = loadModuleFromNodeModulesFolder(moduleName, directory, failedLookupLocations, state);
+                    if (packageResult && hasTypeScriptFileExtension(packageResult)) {
+                        // Always prefer a TypeScript (.ts, .tsx, .d.ts) file shipped with the package
+                        return packageResult;
                     }
                 }
+
+                // Else prefer a types package over non-TypeScript results (e.g. JavaScript files)
+                const typesResult = loadModuleFromNodeModulesFolder(combinePaths("@types", moduleName), directory, failedLookupLocations, state);
+                if (typesResult || packageResult) {
+                    return typesResult || packageResult;
+                }
             }
 
             const parentPath = getDirectoryPath(directory);
@@ -709,7 +719,7 @@ namespace ts {
         const state = { compilerOptions, host, traceEnabled, skipTsx: !compilerOptions.jsx };
         const failedLookupLocations: string[] = [];
         const supportedExtensions = getSupportedExtensions(compilerOptions);
-        let containingDirectory = getDirectoryPath(containingFile);
+        const containingDirectory = getDirectoryPath(containingFile);
 
         const resolvedFileName = tryLoadModuleUsingOptionalResolutionSettings(moduleName, containingDirectory, loadModuleFromFile, failedLookupLocations, supportedExtensions, state);
         if (resolvedFileName) {
@@ -718,18 +728,9 @@ namespace ts {
 
         let referencedSourceFile: string;
         if (moduleHasNonRelativeName(moduleName)) {
-            while (true) {
-                const searchName = normalizePath(combinePaths(containingDirectory, moduleName));
-                referencedSourceFile = loadModuleFromFile(searchName, supportedExtensions, failedLookupLocations, /*onlyRecordFailures*/ false, state);
-                if (referencedSourceFile) {
-                    break;
-                }
-                const parentPath = getDirectoryPath(containingDirectory);
-                if (parentPath === containingDirectory) {
-                    break;
-                }
-                containingDirectory = parentPath;
-            }
+            referencedSourceFile = referencedSourceFile = loadModuleFromAncestorDirectories(moduleName, containingDirectory, supportedExtensions, failedLookupLocations, state) ||
+                // If we didn't find the file normally, look it up in @types.
+                loadModuleFromNodeModulesAtTypes(moduleName, containingDirectory, failedLookupLocations, state);
         }
         else {
             const candidate = normalizePath(combinePaths(containingDirectory, moduleName));
@@ -741,4 +742,20 @@ namespace ts {
             ? { resolvedModule: { resolvedFileName: referencedSourceFile }, failedLookupLocations }
             : { resolvedModule: undefined, failedLookupLocations };
     }
+
+    /** Climb up parent directories looking for a module. */
+    function loadModuleFromAncestorDirectories(moduleName: string, containingDirectory: string, supportedExtensions: string[], failedLookupLocations: string[], state: ModuleResolutionState): string | undefined {
+        while (true) {
+            const searchName = normalizePath(combinePaths(containingDirectory, moduleName));
+            const referencedSourceFile = loadModuleFromFile(searchName, supportedExtensions, failedLookupLocations, /*onlyRecordFailures*/ false, state);
+            if (referencedSourceFile) {
+                return referencedSourceFile;
+            }
+            const parentPath = getDirectoryPath(containingDirectory);
+            if (parentPath === containingDirectory) {
+                return undefined;
+            }
+            containingDirectory = parentPath;
+        }
+    }
 }
\ No newline at end of file
diff --git a/tests/baselines/reference/typingsLookupAmd.js b/tests/baselines/reference/typingsLookupAmd.js
new file mode 100644
index 00000000000..1e99644d489
--- /dev/null
+++ b/tests/baselines/reference/typingsLookupAmd.js
@@ -0,0 +1,18 @@
+//// [tests/cases/conformance/typings/typingsLookupAmd.ts] ////
+
+//// [index.d.ts]
+
+export declare class A {}
+
+//// [index.d.ts]
+import {A} from "a";
+export declare class B extends A {}
+
+//// [foo.ts]
+import {B} from "b";
+
+
+//// [foo.js]
+define(["require", "exports"], function (require, exports) {
+    "use strict";
+});
diff --git a/tests/baselines/reference/typingsLookupAmd.symbols b/tests/baselines/reference/typingsLookupAmd.symbols
new file mode 100644
index 00000000000..8235467daf8
--- /dev/null
+++ b/tests/baselines/reference/typingsLookupAmd.symbols
@@ -0,0 +1,17 @@
+=== /x/y/foo.ts ===
+import {B} from "b";
+>B : Symbol(B, Decl(foo.ts, 0, 8))
+
+=== /node_modules/@types/a/index.d.ts ===
+
+export declare class A {}
+>A : Symbol(A, Decl(index.d.ts, 0, 0))
+
+=== /x/node_modules/@types/b/index.d.ts ===
+import {A} from "a";
+>A : Symbol(A, Decl(index.d.ts, 0, 8))
+
+export declare class B extends A {}
+>B : Symbol(B, Decl(index.d.ts, 0, 20))
+>A : Symbol(A, Decl(index.d.ts, 0, 8))
+
diff --git a/tests/baselines/reference/typingsLookupAmd.trace.json b/tests/baselines/reference/typingsLookupAmd.trace.json
new file mode 100644
index 00000000000..5c83757454c
--- /dev/null
+++ b/tests/baselines/reference/typingsLookupAmd.trace.json
@@ -0,0 +1,59 @@
+[
+    "======== Resolving module 'b' from '/x/y/foo.ts'. ========",
+    "Module resolution kind is not specified, using 'Classic'.",
+    "File '/x/y/b.ts' does not exist.",
+    "File '/x/y/b.d.ts' does not exist.",
+    "File '/x/b.ts' does not exist.",
+    "File '/x/b.d.ts' does not exist.",
+    "File '/b.ts' does not exist.",
+    "File '/b.d.ts' does not exist.",
+    "File '/x/y/node_modules/@types/b.ts' does not exist.",
+    "File '/x/y/node_modules/@types/b.d.ts' does not exist.",
+    "File '/x/y/node_modules/@types/b/package.json' does not exist.",
+    "File '/x/y/node_modules/@types/b/index.ts' does not exist.",
+    "File '/x/y/node_modules/@types/b/index.d.ts' does not exist.",
+    "File '/x/node_modules/@types/b.ts' does not exist.",
+    "File '/x/node_modules/@types/b.d.ts' does not exist.",
+    "File '/x/node_modules/@types/b/package.json' does not exist.",
+    "File '/x/node_modules/@types/b/index.ts' does not exist.",
+    "File '/x/node_modules/@types/b/index.d.ts' exist - use it as a name resolution result.",
+    "======== Module name 'b' was successfully resolved to '/x/node_modules/@types/b/index.d.ts'. ========",
+    "======== Resolving module 'a' from '/x/node_modules/@types/b/index.d.ts'. ========",
+    "Module resolution kind is not specified, using 'Classic'.",
+    "File '/x/node_modules/@types/b/a.ts' does not exist.",
+    "File '/x/node_modules/@types/b/a.d.ts' does not exist.",
+    "File '/x/node_modules/@types/a.ts' does not exist.",
+    "File '/x/node_modules/@types/a.d.ts' does not exist.",
+    "File '/x/node_modules/a.ts' does not exist.",
+    "File '/x/node_modules/a.d.ts' does not exist.",
+    "File '/x/a.ts' does not exist.",
+    "File '/x/a.d.ts' does not exist.",
+    "File '/a.ts' does not exist.",
+    "File '/a.d.ts' does not exist.",
+    "File '/x/node_modules/@types/b/node_modules/@types/a.ts' does not exist.",
+    "File '/x/node_modules/@types/b/node_modules/@types/a.d.ts' does not exist.",
+    "File '/x/node_modules/@types/b/node_modules/@types/a/package.json' does not exist.",
+    "File '/x/node_modules/@types/b/node_modules/@types/a/index.ts' does not exist.",
+    "File '/x/node_modules/@types/b/node_modules/@types/a/index.d.ts' does not exist.",
+    "File '/x/node_modules/@types/node_modules/@types/a.ts' does not exist.",
+    "File '/x/node_modules/@types/node_modules/@types/a.d.ts' does not exist.",
+    "File '/x/node_modules/@types/node_modules/@types/a/package.json' does not exist.",
+    "File '/x/node_modules/@types/node_modules/@types/a/index.ts' does not exist.",
+    "File '/x/node_modules/@types/node_modules/@types/a/index.d.ts' does not exist.",
+    "File '/x/node_modules/@types/a.ts' does not exist.",
+    "File '/x/node_modules/@types/a.d.ts' does not exist.",
+    "File '/x/node_modules/@types/a/package.json' does not exist.",
+    "File '/x/node_modules/@types/a/index.ts' does not exist.",
+    "File '/x/node_modules/@types/a/index.d.ts' does not exist.",
+    "File '/node_modules/@types/a.ts' does not exist.",
+    "File '/node_modules/@types/a.d.ts' does not exist.",
+    "File '/node_modules/@types/a/package.json' does not exist.",
+    "File '/node_modules/@types/a/index.ts' does not exist.",
+    "File '/node_modules/@types/a/index.d.ts' exist - use it as a name resolution result.",
+    "======== Module name 'a' was successfully resolved to '/node_modules/@types/a/index.d.ts'. ========",
+    "======== Resolving type reference directive 'a', containing file '/__inferred type names__.ts', root directory '/node_modules/@types'. ========",
+    "Resolving with primary search path '/node_modules/@types'",
+    "File '/node_modules/@types/a/package.json' does not exist.",
+    "File '/node_modules/@types/a/index.d.ts' exist - use it as a name resolution result.",
+    "======== Type reference directive 'a' was successfully resolved to '/node_modules/@types/a/index.d.ts', primary: true. ========"
+]
\ No newline at end of file
diff --git a/tests/baselines/reference/typingsLookupAmd.types b/tests/baselines/reference/typingsLookupAmd.types
new file mode 100644
index 00000000000..44273c03f80
--- /dev/null
+++ b/tests/baselines/reference/typingsLookupAmd.types
@@ -0,0 +1,17 @@
+=== /x/y/foo.ts ===
+import {B} from "b";
+>B : typeof B
+
+=== /node_modules/@types/a/index.d.ts ===
+
+export declare class A {}
+>A : A
+
+=== /x/node_modules/@types/b/index.d.ts ===
+import {A} from "a";
+>A : typeof A
+
+export declare class B extends A {}
+>B : B
+>A : A
+
diff --git a/tests/cases/conformance/typings/typingsLookupAmd.ts b/tests/cases/conformance/typings/typingsLookupAmd.ts
new file mode 100644
index 00000000000..e452894e9b4
--- /dev/null
+++ b/tests/cases/conformance/typings/typingsLookupAmd.ts
@@ -0,0 +1,14 @@
+// @traceResolution: true
+// @noImplicitReferences: true
+// @currentDirectory: /
+// @module: amd
+
+// @filename: /node_modules/@types/a/index.d.ts
+export declare class A {}
+
+// @filename: /x/node_modules/@types/b/index.d.ts
+import {A} from "a";
+export declare class B extends A {}
+
+// @filename: /x/y/foo.ts
+import {B} from "b";