Kaj Ahlmann (right), owner of the Six Sigma Ranch, Vineyards, and Winery, and vineyard manager, David Weiss, create great wines by applying old-world techniques and the rigor of proven quality improvement.

Some people take it easy when they retire. But Kaj Ahlmann, retired chairman, president, and CEO of General Electric’s Employers Reinsurance division, is just getting started. In 1999, he united two of his passions—wine and statistics—in a new venture: the Six Sigma Ranch, Vineyards, and Winery. This pairing may seem unlikely.

Winemaking conjures images of pastoral fields of lush grapes, grown by experts who divine the ideal time to pick and ferment them. Six Sigma, on the other hand, is frequently associated with mass production, and massaging reams of data to wring maximum efficiency from the factory.

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