This chapter discusses the market ecosystem for companies for developing appropriate marketing strategies that seem fit in the competitive marketplace. The market ecosystem is explained in the chapter in the context of industry attractiveness, consumer behavior, market competition, and innovation and business growth. In addition, the discussion on market segmentation, targeting, and positioning of products and services in the competitive marketplace enriches learning on market environment in this chapter. Discussions in this chapter get into the core of marketing strategy formulation through exploring the external fit of the firm. Types of markets segments, digital marketing, and e-commerce have also been discussed in the chapter. In addition, the classified markets by business attributes (market taxonomy), elements of business canvas, and e-commerce business model have been discussed along with the case studies on market competition and Starbucks, and Amazon e-commerce company.