> ## Documentation Index
> Fetch the complete documentation index at: https://nango.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# eClinicalWorks (FHIR) - How do I connect a practice?

## Overview

To authenticate with eClinicalWorks, you need:

1. **FHIR Base URL** — the practice-specific FHIR R4 base URL, e.g. `fhir4.eclinicalworks.com/fhir/r4/<practice-code>`. Nango uses this as the base for all proxied API calls.
2. **OAuth Server URL** — your practice-specific OAuth authorization server host, used to reach the token endpoint. Nango uses this to request access tokens.

### Prerequisites

* Your practice has approved and activated the developer application in the eClinicalWorks Dev Portal, and your administrator has mapped its Client ID to your practice.

### Step 1: Finding your FHIR Base URL

eClinicalWorks (or your practice's IT/eCW team) provides this when your practice activates the application — it's specific to your eClinicalWorks environment, e.g. `fhir4.eclinicalworks.com/fhir/r4/SANDBOX`.

### Step 2: Finding your OAuth Server URL

eClinicalWorks calls this the issuer URL. Once you have your FHIR Base URL, fetch its `.well-known/smart-configuration` document:

```bash theme={null}
curl https://<your-fhir-base-url>/.well-known/smart-configuration
```

The response includes a `token_endpoint` field, e.g. `https://oauthserver.eclinicalworks.com/oauth/oauth2/token` — your OAuth Server URL is the host portion of that value (`oauthserver.eclinicalworks.com` in this example).

### Step 3: Enter your details in the Connect UI

Once you have both values:

1. Open the form where you need to authenticate with eClinicalWorks.
2. Enter your **FHIR Base URL** and **OAuth Server URL** in the designated fields.
3. Submit the form, and you should be successfully authenticated.

<img src="https://mintcdn.com/nango/DNfjj6cQjoIG6biQ/api-integrations/eclinicalworks/form.png?fit=max&auto=format&n=DNfjj6cQjoIG6biQ&q=85&s=2b58d51d2d6a2c631f937c6adb6b36f5" style={{maxWidth: "450px" }} width="502" height="699" data-path="api-integrations/eclinicalworks/form.png" />

You are now connected to eClinicalWorks.