This chapter reviews a range of concepts associated with the customer, organizational markets and consumer buying behaviour. An understanding of customers and the benefits they seek from an organization is central to marketing. The chapter explores the distinction between organizational and consumer markets, the customer concept in the public sector, consumer behaviour and decision-making and the buying process in organizational markets. It reviews buying process in organizational markets. The chapter focuses on the nature of customers in the public sector, and revisits the societal marketing concept and segmentation and targeting, which can be used to match customers with products or services. The chapter turns its attention to consumers and their behaviour; the traditional consumer behaviour models are interpreted for their relevance to a range of information product or service acquisition contexts. Marketers have explored psychographic or lifestyle segmentation, which seeks to segment consumers not only on demographic characteristics, but also on attitudes to life, beliefs and aspirations, activities and interests.