Thanks for the reply. I've submitted the same question to the forms module developer, and am waiting on a response.   I did have a tech support chat with Constant Contact about the field naming conventions, but the tech appeared to be unfamiliar with questions about the API. Am I correct that the valid property names for contacts are listed in the documentation?   https://developer.constantcontact.com/docs/contacts-api/contacts-index.html#create_contact ... View more