Adventures with direct equity are opening new doors for Australia's four dominant commercial banks. All say they want to make direct equity investments to help win new business and to complement their traditional corporate banking business of lending and debt underwriting.

A challenge for the big banks, however, is managing and living with the additional risk. They want to push further into the terrain of investment banking, but are wary of the additional capital required and the dangers of straying too far from home. The big banks - ANZ Bank, Commonwealth Bank, National Australia Bank and Westpac - have waxed and waned in their appetite to take direct equity in projects where the banks are also debt underwriters.