diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 00000000..1b10f8a0
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,245 @@
+declare module "gdax" {
+    export type callback<T> = (err, response, data: T) => void;
+
+    export type ProductTicker = {
+        trade_id: string,
+        price: string,
+        size: string,
+        bid: string,
+        ask: string,
+        volume: string,
+        time: Date
+    }
+
+    type LimitOrder = {
+        type: "limit";
+        product_id: string;
+        price: string;
+        size: string;
+        time_in_force?: "GTC" | "GTT" | "IOC" | "FOK";
+        cancel_after?: "min" | "hour" | "day";
+        post_only: boolean;
+    };
+
+    type MarketOrder = {
+        type: "market";
+        product_id: string;
+        size: string;
+    } |
+        {
+            type: "market";
+            product_id: string;
+            funds: string;
+        };
+
+    type StopOrder = {
+        type: "stop";
+        product_id: string;
+        size: string;
+    } |
+        {
+            type: "stop";
+            product_id: string;
+            funds: string;
+        };
+
+    export type BuyOrderParams = MarketOrder | LimitOrder | StopOrder;
+
+    export type SellOrderParams = MarketOrder | LimitOrder | StopOrder;
+
+    export type OrderResult = {
+        id: string;
+        price: number;
+        size: number;
+        product_id: string;
+        side: "buy" | "sell";
+        stp: "dc" | "co" | "cn" | "cb";
+        type: "limit" | "market" | "stop";
+        time_in_force: "GTC" | "GTT" | "IOC" | "FOK";
+        post_only: boolean;
+        created_at: string;
+        fill_fees: number;
+        filled_size: number;
+        executed_value: number;
+        status: "received" | "open" | "done";
+        settled: boolean;
+    }
+
+    export type OrderInfo = {
+        id: string;
+        price: number;
+        size: number;
+        product_id: string;
+        side: "buy" | "sell";
+        stp: "dc" | "co" | "cn" | "cb";
+        funds: number;
+        specified_funds: number;
+        type: "market" | "limit" | "stop";
+        post_only: boolean,
+        created_at: string;
+        done_at: string;
+        done_reason: string;
+        fill_fees: number;
+        filled_size: number;
+        executed_value: number;
+        status: "received" | "open" | "done" | "pending";
+        settled: boolean;
+    }
+
+    export type PageArgs = {
+        before: number;
+        after?: number;
+        limit?: number;
+    } |
+        {
+            before?: number;
+            after: number;
+            limit?: number;
+        } |
+        {
+            before?: number;
+            after?: number;
+            limit: number;
+        };
+
+
+
+    export type Account = {
+        id: string,
+        profile_id: string,
+        currency: "USD" | "BTC" | "LTC" | "ETH",
+        balance: number,
+        available: number,
+        hold: number
+    };
+
+    export type CoinbaseAccount = {
+        id: string,
+        name: string,
+        balance: number,
+        currency: CurrencyType,
+        type: "wallet" | "fiat",
+        primary: boolean,
+        active: boolean
+    };
+
+    export type CurrencyType = "USD" | "BTC" | "LTC" | "ETH";
+
+    export type CurrencyInfo = {
+        id: CurrencyType,
+        name: string,
+        min_size: string
+    };
+
+    export class PublicClient {
+        constructor(productId: string);
+
+        getProducts(callback: callback<any>);
+        getProducts(): Promise<any>;
+
+        getProductOrderBook(callback: callback<any>);
+        getProductOrderBook(): Promise<any>;
+
+        getProductTicker(callback: callback<ProductTicker>);
+        getProductTicker(): Promise<ProductTicker>;
+
+        getProductTrades(callback: callback<any>);
+        getProductTrades(): Promise<any>;
+
+        getProductTradeStream(callback: callback<any>);
+        getProductTradeStream(): Promise<any>;
+
+        getProductHistoricRates(args: any, callback: callback<any[][]>);
+        getProductHistoricRates(args: any): Promise<any[][]>;
+
+        getProduct24HrStats(callback: callback<any>);
+        getProduct24HrStats(): Promise<any>;
+
+        getCurrencies(callback: callback<CurrencyInfo[]>);
+        getCurrencies(): Promise<CurrencyInfo[]>;
+
+        getTime(callback: callback<any>);
+        getTime(): Promise<any>;
+    }
+
+    export class AuthenticatedClient {
+        constructor(key: string, b64secret: string, passphrase: string, apiURI: string);
+
+        getCoinbaseAccounts(callback: callback<CoinbaseAccount[]>)
+        getCoinbaseAccounts(): Promise<CoinbaseAccount[]>;
+
+        getAccounts(callback: callback<Account[]>);
+        getAccounts(): Promise<Account[]>;
+
+        getAccount(accountID: string, callback: callback<Account>);
+        getAccount(accountID: string): Promise<Account>;
+
+        getAccountHistory(accountID: string, callback: callback<any>);
+        getAccountHistory(accountID: string): Promise<any>;
+
+        getAccountHistory(accountID: string, pageArgs: PageArgs, callback: callback<any>)
+        getAccountHistory(accountID: string, pageArgs: PageArgs): Promise<any>;
+
+        getAccountHolds(accountID: string, callback: callback<any>);
+        getAccountHolds(accountID: string): Promise<any>;
+
+        getAccountHolds(accountID: string, pageArgs: PageArgs, callback: callback<any>);
+        getAccountHolds(accountID: string, pageArgs: PageArgs): Promise<any>;
+
+        buy(params: BuyOrderParams, callback: callback<OrderResult>);
+        buy(params: BuyOrderParams): Promise<OrderResult>;
+
+        sell(params: SellOrderParams, callback: callback<OrderResult>);
+        sell(params: SellOrderParams): Promise<OrderResult>;
+
+        cancelOrder(orderID, callback: callback<any>);
+        cancelOrder(orderID): Promise<any>;
+
+        cancelAllOrders(args: { product_id: string }, callback: callback<any>);
+        cancelAllOrders(args: { product_id: string }): Promise<any>;
+
+        getOrders(callback: callback<any>);
+        getOrders(): Promise<any>;
+
+        getOrders(pageArgs: PageArgs, callback: callback<any>);
+        getOrders(pageArgs: PageArgs): Promise<any>;
+
+        getOrder(orderID, callback: callback<OrderInfo>);
+        getOrder(orderID): Promise<OrderInfo>;
+
+        getFills(callback: callback<any>);
+        getFills(): Promise<any>;
+
+        getFills(pageArgs: PageArgs, callback: callback<any>);
+        getFills(pageArgs: PageArgs): Promise<any>;
+
+        getFundings(params, callback: callback<any>);
+        getFundings(params): Promise<any>;
+
+        repay(params, callback: callback<any>);
+        repay(params): Promise<any>;
+
+        marginTransfer(params, callback: callback<any>);
+        marginTransfer(params): Promise<any>;
+
+        closePosition(params, callback: callback<any>);
+        closePosition(params): Promise<any>;
+
+        deposit(params, callback: callback<any>);
+        deposit(params): Promise<any>;
+
+        withdraw(params, callback: callback<any>);
+        withdraw(params): Promise<any>;
+
+        getTrailingVolume(callback: callback<any>);
+        getTrailingVolume(): Promise<any>;
+    }
+
+    export class WebsocketClient {
+        constructor(productIds: string[]);
+        on(event: 'message', eventHandler: (data) => void);
+        on(event: 'error', eventHandler: (err) => void);
+        on(event: 'open', eventHandler: () => void);
+        on(event: 'close', eventHandler: () => void);
+    }
+}
diff --git a/package.json b/package.json
index 03f845e8..99be47f1 100644
--- a/package.json
+++ b/package.json
@@ -55,6 +55,7 @@
   ],
   "license": "MIT",
   "main": "index.js",
+  "types": "index.d.ts",
   "repository": {
     "type": "git",
     "url": "git://github.com/coinbase/gdax-node.git"