The redoubtable economist Robert Solow once quipped that you could see the computer age everywhere but in the productivity statistics. Of course, he made that observation in 1987, nearly ten years before companies boosted the productivity of US labor by combining managerial innovation with information technology in an effort to focus on a growing class of economic activities called interactions.

New McKinsey research shows that the nature of US economic activity is shifting again—away from the simpler, rule-based interactions that companies automated during the last half of the 1990s and toward more complex interactions requiring high levels of judgment and deep experience.

The rise of complex interactions will once again bring technology center stage, though not as the kind of labor substitute that fueled the productivity gains of the late 1990s. This time technology will complement the way highly skilled workers—who now make up roughly 40 percent of the US labor market—perform their jobs, by helping them to recognize complex patterns, to solve novel problems, and to manage interpersonal and group dynamics.

Technology, in and of itself, rarely makes labor more productive; managerial innovations are also necessary. As Bradford C. Johnson, James M. Manyika, and Lareina A. Yee point out in "The next revolution in interactions," the use of technology to complement and enhance the work of talented decision makers rather than replace them will require executives to think very differently about the organizational structures that best facilitate their work, the mix of skills a company really needs, and how to hire and develop talent. More broadly, to realize the full value of this second revolution in interactions, policy makers must rethink their approaches to the infrastructure of technology, to competition policy, and to education and training.

High-value employees are also at the core of "Strategy in an era of global giants," by Lowell L. Bryan and Michele Zanini. The authors observe that value in the largest companies increasingly depends on the work of talented professionals who produce and share intangibles through complex interactions. For senior executives, this shift brings a new set of strategic and organizational problems.

The growing importance of complex interactions also informs "Transforming sales and service," by Thomas Baumgartner, Roland H. John, and Tomas Nauclér, who find that sales, sales support, and services make increasingly powerful contributions to many business-to-business purchasing decisions. To respond, companies must revisit their interactions with customers to learn how to serve the low and high ends of the market simultaneously.

Meanwhile, China's economy faces a different sort of problem—one resulting from the greater role of (and demand for) talented workers. Given the country's enormous pool of university graduates, you might be surprised to learn that only a small percentage of them have the skills required for employment in world-class companies, as a new study by the McKinsey Global Institute shows. In "China's looming talent shortage," Diana Farrell and Andrew J. Grant argue that a lack of suitable workers could slow China's rapid economic ascent.

Broad changes in economic activity inevitably create new opportunities to achieve competitive advantage as well as new competitive hazards. The articles in this issue address the implications of those shifts for the companies that best combine technology and managerial innovation.