Is is possible to hide a field on a form for only campaign members? Meaning members of the program won't see the field but if the person is coming from an outside source, social media, referral etc. the field appears?
First, campaign members and program members are actually different things. So to be precise, can you please change the title of the thread, since it seems like you're talking about program members?
To accurately answer your question, can you clarify that you mean if a web session is associated with an existing lead, and that lead is a member of the program the Landing Page is in, can you hide a field? (Spoiler: not out of the box, but I want be sure that's your question.)
Thanks, the lead is a member of the program the LP is in and I would like to hide a specific field on the form housed on the LP but only for program members.
See this other post from today, it's the same underlying need, though you may not realize it until you read my recent comment: Private Event with Restricted Guest List
In your case, you can use the "Program History" field to populate a hidden field on the form, and in turn use that in visibility rules. So it's quite easy once you have the field being maintained. But there's the rub.