The awards, which traditionally recognise the country's best advertising campaigns, included a PR category this year, bestowing gold, silver and bronze prizes.
Burson won the gold accolade for its "changing beer perceptions" campaign aimed at lifting Spain's sagging beer consumption. The effort, devised for the Spanish beer federation Cervezeros de Espana, focused on the beneficial properties of the drink if consumed in moderation. It also boosted sales for 'sin' non-alchoholic beers.
Cervezeros de Espana president Carlos de Jaureguizar accompanied Burson's account director Cristobal Fernandez and other team members to take the price to the cheer of 2,000 spectators. Spanish Communications Secretary Fernando Moraleda was also present at the ceremony.
The Eficacia silver and bronze awards were handed to Weber Shandwick and small PR shop Marco de Comunicacion respectively. Weber was rewarded for a campaign to promote the Hotel Puerta America and Silken Hotels while Marco received the accolade for an event to publizice online dating service Match.com.
The Weber effort "had a spectacular repercussion in the media and sharply increased visits to the hotels," judges said. Marco's initiative boosted Match.com's user numbers to 1.3m from 800,000.
The Eficacia jury comprised 12 PR industry professionals including chief judge Rafael Mazon, marketing and external relations director for Procter & Gamble.