The Texas market, boosted by energy work and a strong economy, has been a big attraction for Big Law firms in the U.S., but now large U.K. and global firms are increasingly launching operations in the Lone Star State, including recent moves by Allen & Overy and Clifford Chance.

Allen & Overy and New York-based Shearman & Sterling announced late last month they have agreed to merge, creating a firm with combined revenue of $3.4 billion and about 3,900 lawyers in 49 offices—including in Austin, Dallas and Houston. The firm will be called Allen Overy Shearman Sterling, or A&O Shearman.