45. Louis Grassi

When the rich and powerful are backed into an economic corner, they turn to their trusted advisor for guidance. There’s a good chance there are a few people on this very list for whom Lou Grassi is that person. Grassi has done more than amass a large firm with an impressive number of accountants; he has managed to become the personal consigliere to an elite cadre of businesspeople on LI. Part of Grassi’s secret to expansion is in his diversification over the past several years. The Grassi Empire goes beyond accounting and now includes management, healthcare and technology consulting firms.