The Indian telecom industry is one of the fastest growing in the world and second largest mobile market globally. The Indian cell phone market is characterized by a large subscriber base (545 million connections as on May, 2010, expected to reach 876.6 million in 2013), low average revenue per user (INR 209 as on March 2009) and high churn rates (53.2% in 2009, and is expected to increase to 59.6% in 2013). The Indian consumers are enjoying a wide range of services along with the world�s lowest local call rates. The mobile phone operators in India are faced with the challenge of reducing customer churn in the ever-increasing prepaid subscriber market. Under such circumstances, the success of mobile phone service providers in India mainly depends on developing innovative schemes to increase customer loyalty. In service organizations, customer loyalty is considered as prime determinant of long-term financial performance of firms. One of the crucial issues of today is to understand how or why a sense of loyalty develops in customers. Loyalty definitions and metrics are mostly in behavioural and attitudinal terms. Consensus is absent in the marketing literature on how loyalty should be conceptualized and measured in the service industry. The present study addresses both the conceptual and measurement issues related to customer loyalty amongst the cell phone users. Building on existing literature, the antecedents of customer loyalty are reassessed in a service setting namely, customer satisfaction, trust, commitment, corporate image, and switching costs. This paper reports the development and validation of scales for measuring customer loyalty and its antecedents. The scale development and validation process was divided into three phases. Phase 1 consisted of the item generation process, assessment of content validity, and initial purification of measures. Item analysis and exploratory factor analysis were used on data collected from 250 postgraduate business students of a major university in India for initial purification of the instrument. In Phase 2, additional data were collected from 855 cell phone users in northern India to assess the latent factor structure through confirmatory factor analysis. In Phase 3, the discriminant validity and convergent validity of the measures were established. The managerial implications of the major findings of this study are as follows: It contributes to the existing literature by developing a theory-based framework for understanding the direct effects of satisfaction, trust and commitment, switching costs and corporate image on behavioural and attitudinal loyalty. By measuring loyalty as composite measure consisting of both behavioural loyalty and attitudinal loyalty, it provides evidence of the multidimensional nature of loyalty construct. Using data collected from mobile phone users, the reliability and validity of the scale are established. The newly refined and validated measures can be used by future researchers to study customer loyalty and its antecedent factors. The loyalty measures developed in this study provides managers with an easy tool to identify attitudinal and behavioural differences among customers. Marketing managers can draw meaningful distinctions between customers who buy out of habit and those who buy because of emotional attachment to the company.