Mulderbosch Vineyards has always been a South African iconoclast—and not just because its longtime winemaker, Mike Dobrovic, quotes Sufi mystic poetry as readily as he tosses around winemaking jargon (don't get him started on sulfur bridge esters). Mulderbosch was launched as an independent producer in the Stellenbosch region in 1989, at a time when most of the local wineries were giant cooperatives. By the mid-1990s, it was receiving international acclaim for its vibrant, complex Sauvignon Blanc, and it's still making news, lately with its ventures in the fledgling South African region of Overberg.

Much of the credit for Mulderbosch's success goes to Dobrovic. His 2004 Sauvignon Blanc ($20) tells us that the winery is in top form. Luscious but vibrant, it mingles classic Sauvignon herbal tones with ripe notes of grapefruit and apricot, wrapping them up in a clean, dry finish.

Recently, Dobrovic and his Mulderbosch partners began exploring Overberg, a cooler region south of Stellenbosch along the Indian Ocean coast, joining well-known producers like Iona and Thelema. Dobrovic has also bought land there for his own Sanctum label, choosing slopes and soils to plant the perfect vineyard for Sauvignon Blanc.

Overberg has already gained a reputation as a hot new area for Shiraz, with wines that offer more finesse (and white pepper spiciness) than those produced by vineyards inland. This shows in the brawny, smoky 2002 Mulderbosch Shiraz ($69), and in the broodingly dark but silky 2002 Sanctum ($65), both made with grapes from already established Overberg vineyards.

Can Mulderbosch's reds come to rival its Sauvignon Blanc? The breakthrough may come with the 2003 wines, says Dobrovic, which will be released in November. "I have been fortunate in 24 years of winemaking to have one vintage like 2003."