Recruiting Bruce Wasserstein as chief executive is a spectacular coup for the house of Lazard. But make no mistake, it is also a high-stakes gamble.

Lazard is badly in need of firm leadership and change. The global partnership of Paris, London and New York has been riven by in-fighting which reached a crescendo this year. The New York business has been deteriorating alarmingly. And the European partners have become increasingly unhappy about the division of the spoils and the power of the New York partners, at a time when Europe has been making all the running.