diff --git a/packages/js-sdk/README.md b/packages/js-sdk/README.md
index abdbdd8a..2beeb366 100644
--- a/packages/js-sdk/README.md
+++ b/packages/js-sdk/README.md
@@ -215,12 +215,15 @@ The SDK instance can be initialized by either providing an `sdkKey` or a full pr
 
 Include `sdkKey` as a string property in the options object you pass to the constructor instance. The SDK will fetch the project configuration from Convert's CDN and will then refresh it every `dataRefreshInterval` milliseconds.
 
+> Note: if you use an authenticated key, then you need to include `sdkKeySecret` as a string property.
+
 ```typescript
 import type {ConvertInterface, ConvertConfig} from '@convertcom/js-sdk';
 import ConvertSDK from '@convertcom/js-sdk';
 
 const convertSDK: ConvertInterface = new ConvertSDK({
   sdkKey: 'xxx',
+  sdkKeySecret: 'xxx', // required when using an authenticated SDK key
   dataRefreshInterval: 300000, // in milliseconds (5 minutes)
   environment: 'staging' // can also be "live"; this is configured in the Convert UI.
 } as ConvertConfig);
@@ -267,6 +270,7 @@ import {LogLevel} from '@convertcom/js-sdk';
 
 const config = {
   sdkKey: '', // either this or 'data' has to be provided
+  sdkKeySecret: '', // required when using an authenticated SDK key
   environment: 'staging',
   logger: {
     logLevel: LogLevel.DEBUG,