One year after the collapse of Lehman Brothers, and as delegates prepare for Sibos 2009, Financial News canvassed the opinions of some of the industry’s most senior and influential executives. They explained the lessons of the past 12 months and how regulators should tackle the challenges ahead.

We asked: 1. What single regulation would you introduce to best reduce risk in the financial markets while causing the least disruption? 2. What regulation currently under consideration is likely to cause the least benefit and the most disruption?