Event planners can send a variety of emails to keep their audience engaged and informed: 1. Save the Date: An initial announcement to inform recipients about the upcoming event. 2. Invitation Emails: Detailed information about the event, including agenda, speakers, and how to register. 3. Reminder Emails: Gentle reminders as the event date approaches to ensure high attendance rates. 4. Thank You Emails: Post-event emails to thank attendees and provide follow-up information such as surveys or future event dates.