Data Mining Techniques to Enhance Customer Lifetime Value Chia-Chia Lin 1.2,a , Dong-Her Shih 2,b 1 117 Chian-Kuo Rd., Sec. 2, Ming-Hsiung, Chia-Yi, 62153, Taiwan. 2 123 University Rd., Sec. 3, Douliou, Yunlin, 64002, Taiwan. a 46cclin@gmail.com, b shihdh@yuntech.edu.tw Keywords: Data mining, Customer Lifetime Vale, Target Marketing Abstract. It is proved by many studies that it is more costly to acquire than to retain customers. Consequently, evaluating current customers to keep high value customers and enhance their lifetime value becomes a critical factor to decide the success or failure of a business. This study applies data from customer and transaction databases of a department store, based on RFM model to do clustering analysis to recognize high value customer groups for cross-selling promotions. Introduction Facing with more complexity and competition in today’s business, companies need to develop innovative marketing activities to capture customer needs and improve customer satisfaction and retention. Recently, IT has been utilized to help companies maintain competitive advantage. Data mining techniques are widely used information technology for extracting marketing knowledge and further supporting marketing decisions. Market basket analysis, retail sales analysis, target market analysis and cross-selling analysis are included in the present. Above all, the purposes of this study are ： (1) Assess customer lifetime value (CLV). (2) Improve customer lifetime value (CLV) by target marketing. (3) Improve customer lifetime value (CLV) by cross-selling. Methodology Company's profile of the case Case company (I company) applies ‘Know-How’ from foreign countries, manages with the prospective tactics with the development of the society, and emphasizes on consumers' demands and service. The target customers are those ranging from 18 to 35 years old mentally with definite taste. Customers are treated with respect caring and professionalism. And the differential management of the pursuit of youth fashion and creation is the key why I company can be attractively constantly. In order to solve the problems, the company proposed “Loyal Plan for I company” which was started in May, 2007. The strategy at the first stage lies in expanding the number of credit card holders. The number of card holders in May, 2007 was 8,399, and that in June was about 17,236. Till December of 2007, the number was about 46,982. However, there were over