Law departments have much more trouble finding competent foreign counsel than finding competent US firms. But the two may often be the same. The Client Advisory, March 2007 of Hildebrandt and Citigroup Private Bank at 5, states that of the 250 largest US law firms, 105 firms have foreign offices (See my post of Jan. 3, 2007 about the presence in France of US firms.). On the other hand, that means over half of the largest US firms do not have a single international office.
There are more lawyers in those offices, however, with a 10% increase from 2005 to 13,707 such lawyers. The cities with the largest percentages of those lawyers were London (28%), Paris (9%), and Hong Kong (5%), followed by Frankfort, Tokyo, Brussels, and Moscow. The point is that many US law departments can obtain foreign legal advice in major markets through their customary US firms.