Here's something I often get asked, so I thought I would share it here:

We're launching a second email newsletter at our company – can I send it to subscribers who are already receiving our existing newsletter?

While it might be tempting to do this as a grow-your-mailing-list-quickly idea – don't. It is a mistake to assume subscribers who signed up for one newsletter you offer will want to receive another from your company. No matter how relevant you think it might be. If people aren't expecting it in their inbox they may view it as taking liberties with the permission they gave you (bad reflection on your company). Perhaps it pushes you over the threshold of 'too frequent' (and they will unsubscribe to everything you send). Or, they don't recognise your brand (or do, and are peeved) and 'report as spam'. Believe me, that's bad news for all aspects of your reputation, including delivery.

I suggest companies approach this as a co-registration project. Use the existing newsletter to introduce the new publication to your readers. Make it easy for them to sign up to it.  Include information about your new offering and a link to an example of it in the next few issues of the existing newsletter. Don't forget to rework your subscribe box in the newsletter to offer sign up to both publications – and also add it into the subscribe box throughout your website.  

denise cox, Newsletter Specialist, Newsweaver