Kaiser Aluminum Added to Russell 2000 Index

FOOTHILL RANCH, Calif.--(BUSINESS WIRE)--

Kaiser Aluminum (NASDAQ: KALU), a leading producer of fabricated aluminum products, today announced that the company has been added to the Russell 2000(R) index.

"Inclusion in the Russell 2000 index will further enhance the company's visibility with investors and institutions, and therefore add value to the company and our shareholders," said Jack A. Hockema, chairman, president and CEO of Kaiser Aluminum.

Russell indexes are widely used by investment managers and institutional investors for index funds and as benchmarks for both passive and active investment strategies. An industry-leading $4 trillion in assets currently are benchmarked to them.

Annual reconstitution of Russell's U.S. indexes captures the largest U.S. stocks as of the end of May, ranking them by total market capitalization. The largest 1,000 companies in this ranking comprise the Russell 1000 and the next 2,000 companies become the Russell 2000.

Kaiser Aluminum is a leading producer of fabricated aluminum products for aerospace and high-strength, general engineering, and automotive and custom industrial applications. The company has more than 2,000 employees and 11 plants in North America and produces more than 500 million pounds annually of value-added sheet, plate, extrusions, forgings, rod, bar and tube. For more information, please visit www.kaiseraluminum.com.

Founded in 1936, Russell Investment Group is a subsidiary of Northwestern Mutual Life Insurance Company. With more than $200 billion in assets under management, Russell serves individual, institutional and advisor clients in more than 40 countries. For more information on Russell indexes, go to www.russell.com.

F-1074

Certain statements in this release relate to future events and expectations and, as a result, constitute forward-looking statements involving known and unknown risks and uncertainties that may cause actual results, performance or achievements of the company to be different from those expressed or implied in the forward-looking statements. Important factors that could cause actual results to differ materially from those in the forward-looking statements include: (a) the effectiveness of management's strategies and decisions; (b) adverse changes in economic or aluminum industry conditions generally; (c) adverse changes in the markets served by the company, including the aerospace, defense, general engineering, automotive, distribution and other markets; (d) the company's ability to complete its expansion projects as planned and by targeted completion dates; (e) the company's ability to meet contractual commitments and obligations to supply products meeting required specifications; (f) the company's inability to achieve the level of cash generation, margin improvements, cost savings, or earnings or revenue growth anticipated by management; (g) developments in technology used by the company, its competitors or its customers; (h) changes in laws, governmental regulations or policies, currency exchange rates or competitive factors in the markets served by the company; (i) customer performance; (j) significant legal proceedings or investigations adverse to the company, including environmental, product liability, safety and health and other claims; and (k) the other risk factors summarized in the company's Form 10-K for the year ended December 31, 2006 and other reports filed with the Securities and Exchange Commission.

Source: Kaiser Aluminum

Released June 25, 2007