Edited by Thane Peterson

Abigail Johnson, heiress to the Fidelity Investments empire founded by her grandfather, has begun her long-anticipated move into Fidelity's management ranks. The 35-year-old billionaire on Friday, Jan. 17, gave up her job as manager of Fidelity's $1.3 billion Trend Fund to become manager of equity investment systems, a newly created position in which she will oversee the $50 million Fidelity spends annually on computer systems used by fund managers and traders. Her initial work will focus on setting up high-speed Internet access to Wall Street research and establishing a computerized global research project.

With a 24.5% stake in the company, Abigail Johnson is Fidelity's largest stockholder. That's double the stake of her father, Fidelity Chairman Edward C. "Ned" Johnson III, who owns 12%. Several hundred Fidelity employees own the rest. Though the elder Johnson, 66, hasn't disclosed his succession plans, his daughter is widely viewed as her father's most likely successor. She serves on Fidelity's board of directors but has not yet been named to the firm's powerful operating committee, headed by her father.

Abigail isn't completely abandoning fund management. She will also take on the role of group leader of Fidelity's Specialized Growth Group, replacing Wil Danoff, manager of the $24 billion Contrafund. In that job, she'll assist the managers of eight funds, including Contrafund, Dividend Growth, Value, and other high-profile funds.

By Geoffrey Smith in Boston