In this article from the NYT, a description of the struggle Mr. Volcker is facing in advancing his reform plan for the banking sector. In a nutshell, this would be a "modern" version of the Glass-Steagall act, separating investment banks from commercial banks.
Mr. Volcker is literally and figuratively a "giant", because of his reputation built during his chairmanship of the Fed. The period in which he defeated the high inflation mounting in the US at the beginning of the 1980s is known as Volcker's disinflation. He now and then hired as an external advisor whenever important reforms are needed, and now he is the head the president’s Economic Recovery Advisory Board. While the Obama team is thinking at maintaining the current setup with heavier regulation (changing capital requirements, highlighting guidelines in payment structure for managers), Mr. Volcker is advocating a simpler system where "no bank would be too big too fail", because in his view: “no form of economic organization can fully contain bouts of destructive speculative euphoria”.