diff --git a/index.js b/index.js
index d923b98..a4122be 100644
--- a/index.js
+++ b/index.js
@@ -103,6 +103,12 @@ module.exports = function requireDir(dir, opts) {
             var path = filesMinusDirs[file];
 
             if (path) {
+                // ignore TypeScript declaration files. They should never be
+                // `require`d
+                if (/\.d\.ts$/.test(path)) {
+                    continue;
+                }
+
                 // if duplicates are wanted, key off the full name always, and
                 // also the base if it hasn't been taken yet (since this ext
                 // has higher priority than any that follow it). if duplicates
diff --git a/package.json b/package.json
index c0a4973..203d3af 100644
--- a/package.json
+++ b/package.json
@@ -7,6 +7,8 @@
 , "devDependencies":
   { "coffee-script": "~1.3.3"
   , "mkdirp": "^0.5.0"
+  , "ts-node": "^1.3.0"
+  , "typescript": "^1.8.0"
   }
 , "engines":
   { "node": "*"
diff --git a/test/simple.js b/test/simple.js
index 31e9458..7fea2c5 100644
--- a/test/simple.js
+++ b/test/simple.js
@@ -17,4 +17,14 @@ assert.deepEqual(requireDir('./simple'), {
     c: 'c',
 });
 
+// now register TypeScript and do it again:
+// note that we include typescript files but not declarations.
+require('ts-node/register');
+assert.deepEqual(requireDir('./simple'), {
+    a: 'a',
+    b: 'b',
+    c: 'c',
+    e: 'e',
+});
+
 console.log('Simple tests passed.');
diff --git a/test/simple/e.ts b/test/simple/e.ts
new file mode 100644
index 0000000..bd0c424
--- /dev/null
+++ b/test/simple/e.ts
@@ -0,0 +1 @@
+export = 'e';
diff --git a/test/simple/f.d.ts b/test/simple/f.d.ts
new file mode 100644
index 0000000..e60ad98
--- /dev/null
+++ b/test/simple/f.d.ts
@@ -0,0 +1 @@
+export const foo: 'bar';