The most popular red varieties of Spain include Tempranillo and Garnacha (Grenache). Whites don't garner quite as much recognition, but there are some regional varieties not to be missed, like Albarino and Verdejo. The popular red regions of Spain include Rioja, known for its outstanding wines of the Tempranillo grape; Ribera del Duero, producing high quality reds from Tempranillo and Garnacha; Galacia, with the sub-region of Rias Baixas, home to the deliciously crisp and floral Albarino grape; and Priorat, a region increasing in popularity with its high-quality cult reds. Other regions of note are Rueda, growing the Verdejo grape, La Mancha, a wide desert region, covered in the most planted white variety in the world, Airen, and Jumilla, making wines based on Monastrell (Mourvedre).

Spain's wine laws are based on the Denominacion de Origen (DO) classification system, devised in the 1930's. A four tiered system, the most basic level is Vina de Mesa (table wine) followed by Vino de la Tierra (country wine), DO and at the top DOC. Currently, only Rioja and Priorat have DOC status, while over 65 DO's scatter the country.

Most DO regions are classified and regulated by how long they age the wines. On a red wine label, one may find the terms Crianza, Reserva or Gran Reserva, denoting the wine's barrel and bottle time. Crianza is usually two years between barrel and bottle (the time in each depends on the DO and/or the winemaker), Reserva up to 4 years and Gran Reserva 5 – 6 years. Classifications of each region and wine are controlled by the region's Consejo Regulador.