diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..3d4305d
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,44 @@
+// Type definitions for node-polyglot v0.4.2
+// Project: https://github.com/airbnb/polyglot.js
+// Definitions by: Tim Jackson-Kiely <https://github.com/timjk>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+
+declare namespace Polyglot {
+    interface InterpolationOptions {
+        smart_count?: number | { length: number };
+        _?: string;
+
+        [interpolationKey: string]: any;
+    }
+
+    interface PolyglotOptions {
+        phrases?: any;
+        locale?: string;
+        allowMissing?: boolean;
+        onMissingKey?: (key: string, options?: Polyglot.InterpolationOptions, locale?: string) => string;
+    }
+}
+
+
+export default class Polyglot {
+    constructor(options?: Polyglot.PolyglotOptions);
+
+    extend(phrases: any): void;
+
+    t(phrase: string): string;
+
+    t(phrase: string, smartCount: number): string;
+
+    t(phrase: string, interpolationOptions: Polyglot.InterpolationOptions): string;
+
+    clear(): void;
+
+    replace(phrases: any): void;
+
+    locale(): string;
+
+    locale(locale: string): void;
+
+    has(phrase: string): boolean;
+}