APCO Worldwide today announced that Citibank and Monroe Capital pumped fresh capital into the No. 3 independent firm, enabling it to buy out minority investor WindRiver and fund growth opportunities.

APCO Worldwide

Margery Kraus, founder/executive chairman, said the transaction renews her firm’s committee to remain independent.

Launched in 1984, Washington-based APCO gained its independence from Grey Global Group in 2004.

Ted Koenig, founder/CEO of Monroe Capital, looks forward to helping APCO identify growth opportunities including potential acquisitions. “It is especially gratifying to support a successful business that is majority women-owned, which is one of our priority areas for investment capital,” he said in a statement.

Citibank has advised APCO for more than a decade.

Investment banker Petsky Prunier and law firms Gibson Dunn and Godfrey Kahn advised APCO on the transaction.

APCO, which is helmed by Brad Staples, generated $120.6M in fee income last year.