The development of POS (Point of Sales) systems for small retailers according to their needs is considered to be important to improve their competitive advantages. However, their financial statuses hinder the adoption of the tailored POS systems. Viewing ASP as a viable solution to provide tailored POS systems for the small retailers, this study develops ASP POS service models for the small retailers. First, this study elicits ASP POS requirements of the small retailers in the following areas: merchandising, pricing, store design and display, customer service, advertising and promotion and personal selling. Then, the requirements are clustered and the clusters are analyzed based on the characteristics of the retailers. Then, ASP service models are proposed according to the needs and profiles of the retailers.