DLA Piper is laying off 21 associates and 100 staff members from its U.S. offices.

The cuts are the second round of layoffs in the law firm’s domestic offices this year. In February, it let go of 80 associates and 110 staffers.

The law firm issued a firmwide memo on Wednesday announcing the reductions. “[D]emand across the legal sector remains soft, and it is increasingly clear that major improvements in the U.S. and global economy will not occur before 2010,” the memo said. It was written by Global Chairman Francis B. Burch Jr., Joint Chief Executive Lee Miller and U.S. Managing Partner J. Terence O’Malley.

DLA Piper also has made cuts in its foreign offices this year, including 24 attorneys in London, nine fee earners in the Middle East and 20 fee earners in Asia. The firm’s reductions are the result of a sharp drop in business that most major law firms have experienced amid the recession. Since January 2008, AmLaw 200 law firms have cut 2,976 attorneys. DLA Piper’s reduction of 101 attorneys in 2009 represents 7.6% of its 1,335 U.S. attorneys.

Layoffs at major law firms occurred mostly in the first quarter of 2009. DLA Piper’s memo on Wednesday said that its reductions in February were designed to avoid cuts later in the year. “Unfortunately, economic weakness has continued,” it said.

While the firm’s “financial position remains strong,” according to the memo, tight management of its cost structure is “essential to compete effectively during these uncertain times.”

DLA Piper, now with 3,593 attorneys worldwide, announced in May that it was reducing first-year associate salaries in major markets from $160,000 to $145,000. At the same time, it announced that it was shifting to merit-based pay for associates instead of basing compensation primarily on years of service. Other law firms, including Baker & McKenzie and Greenberg Traurig, also have slashed attorney salaries.

The firm will hold “town meetings” in its offices Thursday regarding the layoffs, the memo said.