The Instituto dos Vinhos do Douro e Porto (IVDP or Port and Douro Wine Institute) regulates the Port industry in Portugal.

Though it accounts for around one percent of production, vintage port is the flagship wine of all Portugal. In the United States, the Portuguese product, by Federal law pursuant to a treaty with Portugal, must be labelled ""Porto"" or ""Vinho do Porto"" for differentiation.Port"" wines produced outside of Portugal may be labelled with a vintage date, but rarely possess the quality and proven age-ability of true vintage port. This, combined with the skill of the Master Blender, has resulted in Graham's mastering the art of making an outstanding 30 year old tawny port. The wonders of wood: Graham's is one of the last Port companies with its own cooperage team, who care for each cask individually.

In 1890, Graham’s became one of the first companies in Portugal to make wines from their own vineyards in the premium Douro Valley. In 2005, the IVDP prohibited the use of the term ""Vintage Character"" replacing it with the term ""Reserve. Because it has already been exposed to oxygen, an open bottle of tawny resists oxidation the longest of all ports. At the heart of Graham's Port is the famous Quinta dos Malvedos which was completely renovated in 2000 and is now equipped with 3 revolutionary robotic lagares that 'tread' the grapes. In contrast to vintage port's short time in barrel, LBV port is aged between four to six years in barrel, to mature it more quickly.

Red port can be made from many types of grapes (castas), but the main ones are Tinta Barroca, Tinta Cão, Tinta Roriz (Tempranillo), Touriga Francesa, and Touriga Nacional. This, combined with the skill of the Master Blender, has resulted in Graham's mastering the art of making an outstanding 30 Years Old Tawny Port. Fabulous accompaniment to dark chocolate, but can also be enjoyed alone as a dessert in its own right. There is a unique body of English ritual and etiquette surrounding the consumption of port, stemming from British naval custom.