When I'm in the process of building an opt in list full of subscribers that look forward to getting my sales message. It becomes very important which email marketing software I use.

Choosing the right one means that I can craft messages that will build a relationship with my market - and not have to worry about all of the things that can go wrong in a campaign. When I don't have to worry about all of the little things - I can focus on providing quality content to my subscribers. That ultimately leads to the sale.

Choosing the wrong one means it's lights out. There is less of a chance of me being able to build trust with my market. Now my attention is being pulled away from my subscribers.

So what features should you look for in an email marketing campaign software?

Here's my checklist:

1. Easy email list management.

If a customer asks to subscribe or unsubscribe from your list, this should be automated and as quick and easy as possible

2. Easy message list management.

You need to be able to add messages to your marketing campaign quickly and easily. You need to be able to change the order that the messages are sent out if necessary.

3. Instant message sending for those moments when things just won't wait.

You should be able to broadcast a message to your customers using your email marketing campaign software.

4. Pre-designed email message templates.

While designing your own message format is a good aim, it's always useful to have a pre-designed template to work with, if only for ideas (rather than staring at a blank screen, wondering what to design).

5. Custom fields for extra data.

For instance, if a customer was looking for a specific product, you could include this in a custom field and then use that to filter who you mail your messages to.

6. Advanced features so that customers can be moved from one list to another automatically.

For instance, you could move a customer from a pre-sales email marketing campaign once they actually buy the product.

7. Link tracking so that you know which links were clicked on.

You can use this to tweak your messages to get a higher response rate

8. Full reporting capabilities.

See exactly what your email marketing campaign subscribers are doing. This should be available on different levels so that you can get an executive overview or drill down to lower levels.

This list in no way contains every feature that you should have in an autoresponder...I left out a few...But what you've just read is my personal list that I've used successfully online to build my opt in list.