Abstract: There are disclosed processes and systems for interactive opt-in messaging. A mobile phone user may enroll in a content delivery service at the invitation of a broadcast program. A content program may then be delivered to the mobile phone. The content program may include a series of messages having interest content and solicitation content. The solicitation content may include a solicitor phone number. A user of the mobile phone may respond to the solicitation content from the mobile phone without having to re-key the solicitor phone number.