The firms who have submitted proposals are:
In Googling, here's what I've found about each (with no commentary from me):
Ray and Associates were just hired to handle the Houston superintendent search (on a split vote) and are currently doing the Topeka, Kansas search, with some notable recommendations around salaries. They are among three firms that applied to handle the Ohio state superintendent search; they conducted the Michigan state superintendent search earlier this year; that had six finalists and resulted in a Michigan superintendent getting the job. More locally, they handled the Longmeadow search, which resulted in their hiring a former district principal, the superintendent in Hampden-Wilbraham Regional. Last year, they conducted the Palm Beach superintendent search, in which the base fee was nearly doubled by expenses charged to the district, including when they came to be interviewed initially (before being hired). They are conducting the Joliet, IL search, where the question of expenses came up upon their being hired. They led the DeKalb County (GA) search back in 2011, in which two of the three finalists had been searched for their current positions by the firm, which could be an aberration except it came up again in their Fort Worth search earlier this year; Fort Worth eventually hired someone else, after two rounds of a search, both of which yielded a single finalist. They were also the search firm for the Albuquerque superintendent search last spring; the superintendent resigned two months later.
Hazard, Young, Attea, and Associates also have applied to lead the Ohio state superintendent search. Locally, they did the initial vetting of the Boston search; they did the Cambridge search, which had three Massachusetts finalists. They also did the Minneapolis search, which resulted in former Holyoke superintendent Sergio Paez being voted in (though contract negotiations are currently on hold); Paez was one of the three Cambridge finalists. They are currently conducting searches for Bedford, NY; Stamford, CT; Laguna Beach, CA; and Minooka, IL. They are also currently conducting the Los Angeles search, which has now reached the initial interview stage. They conducted the Highland Park, IL search, in which the district hired someone who failed to disclose that she was an associate of the firm; she resigned before starting the job. The district hired an interim superintendent and hired a new search firm. It looks as though that isn't the first time that sort of conflict has come up with HYA.
McPherson and Jacobson are currently conducting searches for Othello, WA; Pleasanton, CA; Rogers, AK; Ottumwa, IA; Grand Island, NE; Rapid City, ND ; Lawrence, KS; and Kyrene, AZ. Last year, they conducted the search for Sequim (WA) superintendent, in which the committee passed on the two finalists and hired their current interim. Similarly, the Learning Community Council in Omaha, NE passed on two finalists forwarded by the firm and hired an interim; they'll have the firm conduct a new search.
Atlantic Research Partners now own parts of what was SUPES Academy in their National Superintendents Academy; SUPES was part of the kickback scandal that engulfed former Chicago Public Schools CEO Barbara Byrd-Bennett; Atlantic has also been consultants for Chicago's school improvement grants (see the first link). Some of the same people (as Atlantic) are involved in Chicago's Acceleration Academies, which are charter schools (see the mention of Distinctive Schools here), and the Sun-Times tracks some connections and contracts back to Ron Huberman, who was CPS CEO prior to Byrd-Bennett. They are currently doing the Brookline superintendent search; Jim Huge, under Huge and Associates, which was acquired by Atlantic last summer, did the Salem search; it appears to be when Atlantic picked up superintendent searches. They do other sorts of school consulting, (appear to focus on it) as well, like the recent Santa Fe, NM study of middle schools, or their drop-out recruitment plan for the same district.