SAN JOSE, Calif., May 10, 2004--Marking a new quality milestone for its internal learning and development programs, KLA-Tencor (NASDAQ: KLAC) once again landed a top spot in Training Magazine's 2004 Top 100 award. Ranked as the fifth best provider of workforce development initiatives in the nation, KLA-Tencor is the only Silicon Valley-based company to be recognized in the upper echelon of this list, joining industry giants IBM, Pfizer, Sprint and Booz Hamilton as a top-five recipient of this elite annual award. The only company in the semiconductor equipment sector to appear in the top 40, KLA-Tencor significantly surpassed the placement of the larger Silicon Valley-based businesses represented in the survey.

This year, the company was singled out for the quality of its executive development program (EDP) and its internal executive mentoring program, both of which are designed to cultivate leadership qualities in the organization's future management personnel. The EDP--an 80-hour program for all directors, vice presidents and general managers worldwide--centers on six organizational competencies: strategic thinking, operational excellence, sales, marketing, program execution and competitive workforce dynamics. These modules are taught by senior KLA-Tencor executives, including the chairman, chief executive officer (CEO) and president. In KLA-Tencor's internal executive mentoring program, former and current members of the board of directors, as well as retired KLA-Tencor executives, serve as mentors to a select group of individuals with the highest leadership potential.

"At the core of KLA-Tencor's learning and development programs is a strong belief in leveraging the skills, knowledge and expertise of senior executives to inspire, motivate and train upcoming executive talent," said KLA-Tencor CEO Ken Schroeder. "We place a high premium on promoting from within, so it makes sense to tap into our top-line management to ignite the ambition and harness the skills of our budding executives. We're extremely proud to be ranked so high again on this list. It's a tribute to the dedicated efforts of our corporate learning group and senior management as they help groom our executives for greater seniority."

KLA-Tencor dedicates significant financial and manpower resources toward its internal development functions, and continued to do so even throughout the recent severe semiconductor industry downturn. Of special note is the fact that of the companies represented in the survey, KLA-Tencor--with a global workforce of just under 5,000--was ranked fourth in devoting the highest percentage of their payroll to their employee development endeavors.

About Training Magazine and the Top 100 Award:
Training Magazine is a monthly professional development publication with a 33-year history of writing for training, human resources and business management professionals in all industries. Its annual Top 100 Award is determined through a series of nominations from employees, peers and the publication's 45,000-readership base, as well as an application review and extensive interview process. Companies are judged, in part, on the following criteria: strategic training goals; evaluative processes and mechanisms; workplace surveys; the number of training professionals within the company; tuition reimbursement; total budget for training; and total number of hours devoted to training.

About KLA-Tencor: KLA-Tencor is the world leader in yield management and process control solutions for semiconductor manufacturing and related industries. Headquartered in San Jose, Calif., with operations around the world, KLA-Tencor ranked #6 on S&P's 2002 index of the top 500 companies in the U.S. KLA-Tencor is traded on the Nasdaq National Market under the symbol KLAC. Additional information about the company is available on the Internet at http://www.kla-tencor.com

Contact:
Meggan Powers
Director Corporate Communications