NEW YORK (Bloomberg) — Morgan Stanley's joint venture with Citigroup Inc.'s Smith Barney will create the biggest group of financial advisers at a time when some investors and brokers are seeking independence from Wall Street titans.

The venture, which New York-based Morgan Stanley will control with a 51 percent stake, would employ 20,390 brokers in more than 1,000 branches. That would surpass the roughly 20,000 at Bank of America Corp., which acquired almost 17,000 in the January 2 acquisition of Merrill Lynch & Co. "Brokerage is such a personal, intimate business that it's defied by the 'thundering herd' concept," said Arthur Levitt, a senior adviser to the Carlyle Group and former chairman of the US Securities and Exchange Commission who serves on the board of Bloomberg LP. "What we're going to see in the brokerage business is breakaways from these managed institutions and the beginnings once more of boutique brokerage firms."