Multinational companies, of course, provide rich opportunities for networking, too—and some are trying to goose the guanxi. Ogilvy Public Relations Worldwide holds an annual party for former employees, many of whom now work for O&M clients, including Lenovo, Johnson & Johnson, and solar-panel maker Suntek. McKinsey has plenty of alumni who have moved into senior posts at major companies and startups. "Obviously, they became a valuable network for us," says Andrew Grant, who runs the firm's China practice in Shanghai