Exhibit 99.1

POWER-ONE ANNOUNCES FOURTH QUARTER AND YEAR-END 2008 RESULTS

Achieves Results within Guidance and Net Income of $0.02 per Share

Camarillo, CA, February 5, 2009

Revenue for the quarter was negatively affected by the difficult market environment and approximately $4.8 million related to the appreciation of the U.S. dollar against European currencies. Bookings of $104.6 million in the fourth quarter of 2008 decreased 15% from bookings of $122.7 million in the fourth quarter of 2007.  The Company ended the fourth quarter of 2008 with approximately $69 million in 90-day backlog, compared to  approximately $76 million for the same period last year.

Gross margin improved to 22.0% in the fourth quarter of 2008 compared with 21.1% in the fourth quarter of 2007, as a result of continued efforts to improve operating efficiencies.  Operating expenses decreased to 21.7% of net sales compared with  23.3% of net sales for the fourth quarter of 2007.

The Company continues to implement aggressive cost reduction actions in response to ongoing demand uncertainty.  As a result, the Company will reduce its global headcount by approximately 1,000, or 22% of the workforce, and will incur charges of approximately $1.3 million related to severance.  The Company expects to recoup the cash severance payments from related salary and benefits savings within three months of being incurred and will realize the substantial majority of the run rate benefit in the second quarter of 2009.

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