Vault Firsthand provides us their list of the Top 50 Consulting Firms. 

I find their weighted formula interesting:

30% prestige
15% culture
15% satisfaction
10% compensation
10% work/life balance
10% challenging work
5% business outlook
5% promotions

Congratulations to these remarkable firms. And to the Collective 54 community, when someone tells you that pro serv firms do not scale, send them this list. For example, BCG, #2, employs 22,000 employees in 90 offices in 50 countries. Professional service firms do scale, and the very best, hyper scale.