Mariner Wealth Advisors, a national, independent wealth advisory firm based in Leawood, Kan., has acquired the New York City-based firm RR Advisory Group LLC, to bring its assets under management to $8.2 billion, Mariner announced Monday.

With approximately $780 million in assets under management, RR Advisory Group is an independent wealth management firm with a staff of 20 professionals. The RR Advisory Group management team and advisors will continue to direct the day-to-day operations of the firm, which will continue to be headquartered in New York City.

Terms of the acquisition were not released.

Mariner also recently launched Mariner Trust Company, which supports the firm’s clients with trust and estate planning solutions.