The global advertising industry has experienced significant consolidation, with a few giant communications companies owning most of the major advertising, branding, public relations, digital marketing, marketing research, and other marketing services agencies. Visit the websites of the four largest communications groups, www.wpp.com, www.interpublic.com, and www.publicis.com. From the information they provide about their companies, create a short list of 5 to 10 global advertising agencies that a global marketer might consider working with to create a global advertising campaign and to provide advertising services in most major countries.