【Abstract】CRM (Customer Relationship Management) is a set of strategies that enterprises use to better understand and serve customers, and build a long-term profitable relationship with customers.  In the age of online and mobile services, social media, and accumulation of very large customer data, data mining has been playing an important role in CRM.  More specifically, data mining has been successful applied in all main tasks of CRM, such as customer acquisition (e.g., mining customer profile for direct marketing), customer services (e.g., sequence mining for cross and up selling), and churn prevention (e.g., action mining).  I will then discuss in details how we have successfully applied data mining to CRM to effectively improve customer experience and profit for the enterprises (including banks, insurance and software companies in Canada and US).