---
title: Clinical Direct Messaging Message Flow
slug: net2net-rest/guide/clinical-direct-messaging-message-flow
docTags: 
createdAt: 2026-06-12T09:48:23.745Z
---

The Surescripts Clinical Direct Messaging service enables secure communication of clinical information between providers of healthcare services utilizing the Surescripts network. Network-based routing and electronic message delivery is included with this service. Customers may extend their delivery options by contracting for Guaranteed Delivery of *Clinical Direct* messages. Guaranteed Delivery adds fax and postal mail delivery of *Clinical Direct* messages to the recipient of the electronic message.

### Electronic Routing

A *Clinical* message can be delivered to specified recipients electronically. Electronic message routing uses HTTP (Hypertext Transfer Protocol), a request-response protocol. For each message that is sent, a response message is returned. The status of the delivery of the message is defined by the type of the response (e.g., 000 = pending, 010 = success, 600 = error, etc.).

Within the HTTP request-response protocol, it is preferred that the response from the request be a *Status 010* or *Error* response instead of a delivery of the *Status 000* response with a subsequent freestanding Verify/Error.

The maximum allowable size for a message, including attachments, is restricted to 20MB.