Most business owners would not dream of sharing their skills and secrets with competitors. But Robert Mondavi, the renowned Californian vintner who died last week at the age of 94, took a different view.

Keen to enhance the reputation of California's Napa Valley, home of the winery that made Mondavi's name, he was a firm believer in co-operating with other winemakers and ex-changing ideas. While some rivals were aghast at the prospect of collaborating, the spirit of openness that he championed was a significant factor in the region's rise to the forefront of US winemaking.