Basecamp — 37signals' Launchpad identity — signs users in with the account they use for Basecamp projects. It fits integrations and reporting tools built around those projects.

## Copy the redirect URI

In the [Authdog console](https://console.authdog.com), select the project and environment, open **Authentication > Providers**, find **Basecamp**, and click **Enable**. Copy the redirect URI shown in the form:

```url
https://identity.authdog.com/api/v1/callback/<connectionId>
```

## Create the application

1. Open [37signals integrations](https://integrate.37signals.com/) and register an application.
2. Fill in the name, company, and website.
3. Under **Redirect URI**, paste the redirect URI from Authdog.
4. Save, then copy the **Client ID** and **Client Secret**.

## Configure Authdog

| Field | Value |
| --- | --- |
| **Client ID** | The client identifier from the provider |
| **Client Secret** | The client secret from the provider |

Save, then toggle the connection **active**.

## What Basecamp returns

Authdog requests the provider's default scopes and reads the profile from `https://launchpad.37signals.com/authorization.json`.

The authorization endpoint returns the identity — id, name, email — plus the list of accounts (Basecamp installations) the user can reach.

A user with access to several Basecamp accounts still has one identity. Pick the account explicitly in your product rather than assuming the first one.

## Test it

1. Open your environment's hosted sign-in page, or link to `https://identity.authdog.com/api/v1/signin/<connectionId>`.
2. Select the Basecamp button and complete the flow.
3. Confirm the user appears under **Users** in the console with a Basecamp identity linked.

## Troubleshooting

| Symptom | Cause |
| --- | --- |
| `invalid_request` | The redirect URI does not match the registered value |
| Redirect or callback URL error | The URI registered with the provider does not match Authdog's exactly |
| Works in one environment only | Each environment has its own `connectionId`, and so its own redirect URI to register |

## Related

| Read | To learn how to |
| --- | --- |
| [Connectors](/docs/connectors) | Set up any other social provider |