Accounting firm Parente Randolph has merged with two other firms: Altenburger, Uris, Caglioti & Heyman, and William R. Hoffman Ltd.

Kahn, Litwin, Renza & Co., has merged in Sullivan Shuman & Freedberg, allowing KLR to build its presence in the Greater Boston area.

Accounting firm consolidator cbiz has agreed to acquire Mahoney Cohen, a New York-based CPA and business advisory firm, in an acquisition that is expected to contribute about $55 million in annual revenue.Terms were not disclosed. At press time, the deal was scheduled to close Dec. 31.

Accounting firm Rives & Associates has merged in Allen & Woodall, another firm in North Carolina.

PricewaterhouseCoopers believes that M&A activity will be dominated in 2009 by "mergers of necessity" as distressed companies seek the protection of more stable parents.

Accounting firm Moore Stephens Frost has changed its name to Frost, PLLC.

CBIZ is acquiring Tofias in a deal estimated at $55 million as the accounting provider expands its reach across the Northeast to the New England area.

Local Maryland accounting firms DeLeon & Stang and Berger & Hillman plan to merge at the end of the year.

Regional New York firm Citrin Cooperman said it would merge in Syosset, N.Y.-based Massella & Associates CPA, PLLC, and the SEC Solutions Group LLC effective Jan. 1, 2009.

CPA and business advisory firms Rucci Bardaro & Barrett PC headquartered here, and Lexington, Mass.-based Mathias Barnes & Henshaw P.C. have merged their practices, effective immediately.

California accounting firms Burr Pilger Mayer and Andersen & Co. plan to merge on Jan. 1, 2009.\

Weaver and Tidwell is merging with Polansky McNutt Perry & Co., expanding Dallas-based Weaver into the San Antonio market.

Thomson Reuters has signed an agreement to acquire Paisley, a software developer that specializes in governance, risk and compliance software, especially for Sarbanes-Oxley compliance.

CPA firm Cottrill Arbutina Professional Services has acquired an eight-person tax and audit group from S.R. Snodgrass, expanding its reach in Western Pennsylvania and its auto dealership client base.

CBiz has signed a deal to acquire Mahoney Cohen, a New York-based accounting firm that is expected to contribute about $55 million in annual revenue next year.

Reilly, Penner & Benton said it has merged with another Wisconsin accounting firm, Ragsdale, Spitz & Reuschlein.

The National Association of Certified Valuation Analysts, promoter of the Certified Valuation Analyst credential, has purchased the National Litigation Consultants Review, a newsletter that caters to testifying financial experts.

Net@Work, a high-volume Sage reseller, has acquired Business Technology Solutions, a North Carolina-based VAR specializing in Sage MAS 90 and MAS 200, as well as Abra HRMS Accounting and Human Resources.

The Rehmann Group accounting firm said it plans to merge with another Michigan firm, Pridnia LaPres, effective Jan. 1, 2009.

RSM McGladrey has acquired Philadelphia accounting firm Simonson Lipschutz & Fogel for $6 million.