Depending on your e-commerce project you may have a need to have a CRM solution. If you have a suite of products and services where you want the option of following up with the customer, using a CRM system can make this process flow very well.

Something as simple as being able to keep notes on a client in a field somewhere in their records could be well enough for a customer service representative to review the customer and get a feeling for how their experience has been going. In fact at some point a customer order will get messed up and the more information a customer service representative has the more likely they can maintain a good relationship with that customer.

Marketing to your existing customers is an easy way to get more sales with a little investment. It could be as simple as sending an e-mail to the existing customers. Make sure you offer an opt out link in your e-mails that go out to customer.

This is a simple link that allows them to unsubscribe from the list. You can use your existing software usually to manage these kinds of campaigns.

There are a number of CRM system available on the market.:

Salesforce.com
SageCRM.com
Microsoft Dynamics CRM

SugarCRM
Zoho
ACT - really more of contact manager but the right answer for some