Tourism companies, like other companies producing goods and/or services, practice different strategies to achieve competitive advantage and satisfy the needs and wants of customers/guests. The most important recent strategy is electronic customer relationship management (e-CRM). In today's competitive environment, a successfully implemented e-CRM enhances a customer centric culture that is key to tourism growth and competitive advantage. For tourism companies, e-CRM succeeds only if it is totally integrated strategically and operationally in the business and in the information system of the company. This chapter focuses on e-CRM concept, its importance in tourism, dimensions of e-CRM, major challenges of e-CRM and its opportunities for companies, its implementation in tourism, e-CRM Technologies used in tourism, e-CRM success factors, and the reasons of e-CRM failures.