1) Assume that only text email is supported. 2) Let the user tell you if they want to get HTML email. 3) In the message (regardless of what format they receive) put a link so they can view the contents online in a web browser 4) In the HTML version, put a link that people can click on to switch back to text version; when they click it, reset their value and re-send the email in text form. Think that about covers it. BTW - what if they're reading your html formatted email "off-line" where the images are not available? Or they set up their email client to not load/display images? How does your message look then? (try it out and see) For what it's worth, the email client I have at work does not display images in any html-formatted email, and often these types of email messages appear as long vertical columns about 10-15 chars wide - totally unreadable.