# Voice Calls API
## Overview
Voice Calls API makes it possible to initiate, receive, and control voice calls using a REST API.
## API Access
The following API requests can only be made using a valid access key, and attached to an access role, with an access policy that at least specifies the permissions to the resources outlined in each section below. Learn more about [API access](https://docs.messagebird.com/api/api-access).