This chapter studies the nature of the policy field and its impact on business-lobbying in the EU. Drawing from theories on institutional legitimacy and information-access it observes the variation in density and diversity across regulatory and (re)distributive policy fields, and committee hearings. Empirically, the chapter employs business group surveys, conducts meticulous analysis of a population of 12,000 interest groups lobbying preferences across multiple policy fields assessing their density and diversity as well as their clustering. It includes a case study on business diverse coalition building focusing on net neutrality. Finally, the chapter observes the distribution of business interests across the European Parliament’s committee hearings. In doing so, this chapter contributes to discussions on legitimacy and public policy, chameleon pluralism, business mobilization, and the nature of the policy good.