The main problem is that in recent years the concept of partnership has been stretched to fit a new business model.

ECONOMIST: Professional services

Best Buy entered into a partnership with the mobile phone retailer in 2010 with plans to open 200 stores and expand the concept under the Best Buy banner in the U.S. with standalone stores.

FORBES: Where Best Buy Went Bad

The other concept, pursued by Pfizer, Japan's Ono Pharmaceutical, the AstraZeneca-Renovis partnership and numerous other firms, is to find a brain-cell protector that could be used to stabilize nerve cells and prevent further damage.

FORBES: Brain Repair

However, Lazard is still far from the one-firm concept perfected, for example, by Goldman Sachs, an investment bank that last month abandoned its partnership structure and became a public company.

ECONOMIST: Investment banking