tom johnsonTom Johnson, who leads Abernathy MacGregor's M&A practice and serves as co-president, has been named CEO of the firm, succeeding co-founder Jim Abernathy.

Abernathy had led the firm since co-founding AbMac with James MacGregor in 1984. He called building the firm "one of my life's greatest accomplishments." He said Johnson "embodies our culture and collective drive," adding that 2015 was the firm's most successful year.

Johnson called the appointment "humbling." He handled the Cigna-Anthem merger, Coty's acquisition of P&G's beauty business and the Office Depot-Staples tie-up among other recent deals.

Johnson is a former editor-in-charge of the North American investment banking and finance desk at Reuters. He also ran its M&A and IPO units after stints at CNN Financial News and Baltimore's Daily Record.

Upper management remains in place at the firm, include president Chuck Burgess, COO Carina Davidson, and vice chairs Ian Campbell and MacGregor.