By Tricia Oliveira

Dolce & Gabbana celebrated the 20th anniversary of their first men's collection with two impressive and cleverly contrasting runway shows. To add to the glorious celebration of their golden anniversary, the Italian label brought in singer Annie Lennox, who performed on a grand piano during the runway show on 19 June Saturday.

The duo went elegantly colonial in this Spring 2011 collection, opening with two dandies in tropical white suits, ideal for a partying plantation owner. Collarless shirts, rope belts and sandals and generously cut linen shorts summed up the lazy beachside mood of this show.

On Saturday evening, Stefano and Domenico then held court as they greeted guests for the opening of their retrospective stage inside Palazzo Marino, Milan’s City Hall.

"They might come from Sicily, but Dolce & Gabbana have helped make their adopted city a very famous fashion capital, which makes all us Milanese very proud," Mayor Letizia Moratti said.

Two days later, 21 June Monday, Dolce & Gabbana unveiled their junior collection, D&G, whose theme for next spring was "Le Dejeuner sur l’Herbe".

Starring models with huge tote bags, packed with picnics and baguettes of French bread, and young men in mega gingham shirts, this was as easy going a mood as, well, a summer lunch on a grass verge beside a lazy river.

But their happiest moment was probably their exhibition, which made them the first designers honored with an exhibition in Milan’s historic city hall.

From their opening show in 1990 - which featured rugged country pants, farmer dandy white shirts and flat hunting caps – the pair have built a billion dollar business by bringing "Sicilian Style" to the wardrobes of the world. They helped revolutionize fashion with the first super destroyed designer jeans, and built a huge underwear division by using Italian soccer stars in their campaigns, famously shot in football ground dressing rooms.

Images of the pair’s path-breaking underwear campaigns were also in the show, although Italy drawing against New Zealand at the weekend in the World Cup – in a team that featured all five of the Dolce models in the latest ad – did darken the mood a touch.

But only a tad.

"We began making men’s fashion because we literally could not find the clothes we wanted. At the time we were buying Japanese jeans and stocking up in boutiques for Catholic priests!" smiled Gabbana, as guests tippled on Cinzano gold in the palazzo’s elegant courtyard.