diff --git a/types/cosmiconfig/cosmiconfig-tests.ts b/types/cosmiconfig/cosmiconfig-tests.ts
new file mode 100644
index 0000000000..2676c58407
--- /dev/null
+++ b/types/cosmiconfig/cosmiconfig-tests.ts
@@ -0,0 +1,41 @@
+import cosmiconfig = require("cosmiconfig");
+
+const asyncExplorer = cosmiconfig("yourModuleName", {
+    packageProp: "yourModuleName",
+    rc: ".yourModuleNamerc",
+    js: "yourModuleName.config.js",
+    rcStrictJson: false,
+    rcExtensions: false,
+    stopDir: "someDir",
+    cache: true,
+    sync: false,
+    transform: ({ config, filePath }) => ({ config, filePath }),
+    format: "js"
+});
+
+Promise.all([
+    asyncExplorer.load(),
+    asyncExplorer.load("start/search/here"),
+    asyncExplorer.load(null, "load/this/file.json")
+]).then(result => result);
+
+asyncExplorer.load().then(({ config, filePath }) => ({ config, filePath }));
+
+asyncExplorer.clearFileCache();
+asyncExplorer.clearDirectoryCache();
+asyncExplorer.clearCaches();
+
+const syncExplorer = cosmiconfig("yourModuleName", {
+    packageProp: "yourModuleName",
+    rc: ".yourModuleNamerc",
+    js: "yourModuleName.config.js",
+    rcStrictJson: false,
+    rcExtensions: false,
+    stopDir: "someDir",
+    cache: true,
+    sync: true,
+    transform: ({ config, filePath }) => ({ config, filePath }),
+    format: "js"
+});
+
+const { config, filePath } = syncExplorer.load();
diff --git a/types/cosmiconfig/index.d.ts b/types/cosmiconfig/index.d.ts
new file mode 100644
index 0000000000..032f570d6f
--- /dev/null
+++ b/types/cosmiconfig/index.d.ts
@@ -0,0 +1,63 @@
+// Type definitions for cosmiconfig 4.0
+// Project: https://github.com/davidtheclark/cosmiconfig
+// Definitions by: ozum <https://github.com/ozum>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+// TypeScript Version: 2.2
+
+interface Result {
+    config: object;
+    filePath: string;
+}
+
+interface Options {
+    packageProp?: string | false;
+    rc?: string | false;
+    js?: string | false;
+    rcStrictJson?: boolean;
+    rcExtensions?: boolean;
+    stopDir?: string;
+    cache?: boolean;
+    transform?: (result: Result) => Promise<Result> | Result;
+    configPath?: string;
+    format?: "json" | "yaml" | "js";
+}
+
+// Default is false and makes load() method async
+interface AsyncOptions extends Options {
+    sync?: false;
+}
+
+// Makes load() method sync
+interface SyncOptions extends Options {
+    sync: true;
+}
+
+interface Explorer {
+    clearFileCache(): void;
+    clearDirectoryCache(): void;
+    clearCaches(): void;
+}
+
+interface AsyncExplorer extends Explorer {
+    // You should provide either searchPath or configPath for load method. To disallow both, overloaded definitions added.
+    load(searchPath?: string): Promise<Result>;
+    load(searchPath: null | undefined, configPath?: string): Promise<Result>;
+}
+
+interface SyncExplorer extends Explorer {
+    // You should provide either searchPath or configPath for load method. To disallow both, overloaded definitions added.
+    load(searchPath?: string): Result;
+    load(searchPath: null | undefined, configPath?: string): Result;
+}
+
+declare function cosmiconfig(
+    moduleName: string,
+    options: SyncOptions
+): SyncExplorer;
+
+declare function cosmiconfig(
+    moduleName: string,
+    options?: AsyncOptions
+): AsyncExplorer;
+
+export = cosmiconfig;
diff --git a/types/cosmiconfig/tsconfig.json b/types/cosmiconfig/tsconfig.json
new file mode 100644
index 0000000000..6f0f0ac3a2
--- /dev/null
+++ b/types/cosmiconfig/tsconfig.json
@@ -0,0 +1,16 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "lib": ["es6"],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "strictFunctionTypes": true,
+        "baseUrl": "../",
+        "typeRoots": ["../"],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": ["index.d.ts", "cosmiconfig-tests.ts"]
+}
diff --git a/types/cosmiconfig/tslint.json b/types/cosmiconfig/tslint.json
new file mode 100644
index 0000000000..3db14f85ea
--- /dev/null
+++ b/types/cosmiconfig/tslint.json
@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }