According to the tables, the value of completed M&A deals in Australia and New Zealand is up 26.1 per cent compared to last quarter, and up 322.9 per cent compared to the same period last year.

Despite recent caution over the Greek debt situation, there has been strong deal activity across multiple sectors - something which Freehills partner Rebecca Maslen-Stannage said is cause for optimism

"There's no doubt over the past month or two there's caution creeping in. If you speak to the investment banks they're much more negative at the moment. But mining has continued to be strong and we've had the return of private equity. Another sector having pretty significant transaction activity ... is property," Maslen-Stannage told Lawyers Weekly.

According to Thomson's tables, Freehills advised on the highest value of completed M&A deals (being $US44, 837 million [$41,918 million] in the Asia-Pacific, Australia and New Zealand) in the first half of 2011. Freehills also ranked first based on the number of completed and announced M&A deals (41 and 46 respectively).

"If you continue to do the good deals, it becomes easy to get the good deals," said Maslen-Stannage.

"It's a very competitive market in Australia, it always has been. Freehills puts so much emphasis into M&A as a firm and has relationships that have been built up over a number of years. Once you get a certain momentum up it becomes much easier to get the work in, because people want the same lawyers."

Freehills' corporate group has already acted on a number of major deals in 2011, including the sale of Centro's US assets to Blackstone, and Rio Tinto's takeover offer for Riversdale. The firm increased the value of its announced deals by 9.6 per cent from last year, jumping to second from its ninth placing in 2010.

Allens Arthur Robinson replaced Blake Dawson as the leading firm by value for announced deals and retained a ranking of fourth in value of completed deals. Blakes dropped to sixteenth for announced deal value this year and also dropped to ninth from its prior third place for completed deal value in 2010.

Global firms Skadden, Simpson Thacher & Bartlett and Norton Rose all ranked significantly higher than last year in completed and announced deal value, consolidating their presence in the market but seemingly posing no threat to Australia's national firms.

"We've always competed with global firms so we don't see their rise as a significant development for our M&A work," said Maslen-Stannage.

The Bloomberg league tables, which take into account M&A deals including divestitures, spin-offs, debt-for-equity-swaps, joint ventures, private placements of common equity and convertible securities, told a slightly different story. When it came to ranking firms by deal count, Minter Ellison (34) narrowly pipped Freehills (31) and Allens Arthur Robinson, Clayton Utz and Mallesons Stephen Jaques rounded out the top five.