The Boston company's first-quarter income was $36.6 million, or 93 cents per diluted share, up from $35.2 million, or 81 cents per diluted share, during the same period in 2006.
Cash earnings per share, which exclude amortization and deferred taxes related to intangible assets, rose to $1.43 from $1.27 a year ago.
The results surpassed Wall Street's expectations; analysts surveyed by Thomson First Call had been looking for net income of 91 cents a diluted share.
AMG's assets under management rose 23% during the first quarter to approximately $250 billion from $203 million a year earlier, through a combination of market appreciation and new money from investors. Additional contributions from clients accounted for $34 billion, or 17 percentage points, of the growth.
CEO Sean M. Healey said in a press release that assets in the company's alternative investments and international equities will continue to be particularly strong.
Clients added $1.9 billion of new money during the first quarter, with $2.2 billion going to institutional accounts, $133 million to mutual funds, while wealthy individuals and families pulled a net $446 million of funds from accounts with AMG's subsidiaries.
AMG operates several investment management firms. The company said that its international equities, which include Tweedy, Browne and Genesis, enjoyed robust investment returns in their global and emerging markets offerings.
Healey said in the release that he expects the company's alternative investments will continue to be among its fastest-growing offerings.