Electronic Commerce (eCommerce, i.e. the execution of business processes using Internet technologies) continues to be a significant, pervasive issue for both enterprises and customers. Similarly, mobile commerce (mCommerce, i.e. the execution of business processes using mobile technologies) is gaining momentum again. Management of relationships between enterprises and customers has often been referred to as Customer Relationship Management (CRM). We define CRM as an interactive process that achieves an optimum balance between corporate investments and the satisfaction of customer needs to generate the maximum profit. Fundamentally CRM concerns attracting and keeping "economically valuable" customers and repelling and eliminating "economically invaluable" ones. The amount of information relevant in CRM processes can only be handled effectively when information technology is applied. Due to the lack of personal contact, CRM is of particular importance in eCommerce and mCommerce.