If you want to integrate with Marketo via the ReST API, you will want to create a custom service. Here is how:
Under Admin click on LaunchPoint.
Under New, click New Service.
Enter a Display Name for the service. Select the API Only User previously created.
Oh yeah! The service is now created, let's go ahead and get all the credentials to provide for access.
Credentials for API Access
Under Admin, click on LaunchPoint.
Click View Details for the custom launchpoint service created above.
Click Get Token.
Provide the Client Id, Client Secret,Authorized User and Token to the person in charge of establishing the connection.
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