Differences between oenologist, sommelier, wine merchant?
Quick answer
An oenologist is the wine scientist (winemaking), a sommelier is the service expert (restaurant), and a wine merchant (caviste) is the specialist retailer (sales and advice). Three complementary professions around the same product.
Detailed answer
These three wine professions are often confused, but they correspond to very different roles.
An oenologist (from the Greek oinos, wine, and logos, science) is a scientist. Holding a DNO (National Oenology Diploma) after 5 years of study (bachelor's + master's), they oversee winemaking: chemical analysis, fermentation, blending, ageing. They work in the winery, not the dining room. Belgium has no DNO programme — aspiring oenologists study in France (Bordeaux, Montpellier, Reims).
A sommelier is a wine service professional in the restaurant industry. Their mission: build the wine list, advise guests, manage the restaurant cellar, and deliver impeccable service (temperature, glassware, decanting). Training: hospitality school plus certifications (WSET, CMS). Sommeliers possess encyclopaedic knowledge of regions, grapes, and vintages.
A wine merchant (caviste) is a specialist retailer. They select wines from producers, set up their shop, advise private and professional clients, and sometimes organise tastings. No mandatory qualification in Belgium, but wine knowledge, business acumen, and regulatory awareness are essential.
In short: the oenologist makes the wine, the sommelier serves it, and the caviste sells it. Career crossovers are common: many sommeliers become wine merchants, and some oenologists open their own estates.