To enable the integration between Circa and Marketo, go to your Workspace Settings > Integrations > Marketo. Note that you will need to be a Workspace Admin to access the Integration settings.
Follow the steps to create a new Marketo authentication. Your API endpoint domain can be found by Navigating to Marketo Dashboard > Admin > Web Services. 
For both Client ID and Client Secret, you must create a custom service within Marketo first. More information on creating custom services here.
Your integration can be verified under the Authentication tab. Your connected profile should look like this:
Permissions
To use the Marketo integration, you'll need a Marketo edition that supports API access and, depending on the Marketo sync options you want to use, your Marketo admin will need the following permissions:
- Read/write access to Leads
- Read/write access to Contacts
- Read/write access to Campaigns
- Read/write access to Campaign Members
- Read-only access to Accounts
We recommend creating an "Integration User" – a dedicated Marketo account with name and email address, such as:
- Circa Sync event@yourcompany.com
With this approach, your team can clearly see that updates to synced Campaigns, Contacts and Meetings come from Event.