The renovation of working class areas, designs for times of economic crisis and the reconstruction of cities following natural disasters like earthquakes and tsunamis have taken centre stage at the world's largest architecture fair.
There was a stir as the festival, which runs until November 25, got under way when dozens of local activists occupied the Russian pavilion -- a temple to hi-tech at which visitors are given iPads through which to view the exhibition.
Activists wore balaclavas in support of jailed punk band Pussy Riot.
The awards ceremony went ahead as scheduled however with the Japanese pavilion winning the Golden Lion for best national participation with a series of designs for reconstruction in the wake of last year's tsunami.
The best project award went to "Torre David/ Gran Horizonte" a project by the architectural collective Urban Think Tank about an occupied 45-floor office tower in Caracas that has been turned into a creative community.
The designs housed in the spectacular Arsenale -- an old naval shipyard and military base -- and the nearby Giardini park on the lagoon include some by leading architects including Norman Foster, Zaha Hadid and Renzo Piano.
"The crux is to mend the fracture between architecture and civil society," Biennale president Paolo Baratta said.
This year's theme is "Common Ground" -- intended as interaction between architects and the population as well as between designers themselves.
The exhibition has been put together by British architect David Chipperfield -- most famous for his work on Museum Island in Berlin -- and spreads out over 10,000 square metres (107,600 square feet) with a total of 119 participants.
Among the most eye-catching projects is the installation by Japan's Kazuyo Sejima for the reconstruction of Mijato-jima island, destroyed by the tsunami.
Chile decked out its pavilion to look like the inside of a salt mine, importing 11 tons of salt from the Tarapaca mine especially for the show.
Italy chose to celebrate its history of innovation with a show that goes back to the work of technology pioneer Adriano Olivetti in the post-war period.
The Greek pavilion meanwhile invites visitors to reflect on the transformation of public buildings and spaces during the economic crisis.
One of the novelties this year is the Mexican pavilion outside the 16th century deconsecrated church of San Lorenzo which has been granted to Mexico as its cultural hub for the next nine years on condition that it pays for repairs.
The fair hosts a total of 55 countries taking part including several newcomers like Angola, Kosovo, Kuwait and Peru.
Among other renowned architects showcasing their designs are Jean Nouvel from France, Peter Eisenman from the United States and Ai Weiwei from China.
For weary visitors, "Urban Think Tank" has even set up a replica of a typical Venezuela roadside shack with neon signs, pumping salsa music and unfinished walls that serves up genuine Latin American fare.
The curator of the official Venezuelan pavilion said she did not approve.
"It is an interesting idea but it distorts reality because it is a reductive vision," Adreina Agusti told AFP, as she showed off an exhibition of social housing projects planned by the government of President Hugo Chavez.
Festival organisers on Wednesday also awarded a lifetime achievement award to Alvaro Siza Vieira, famous for works such as the Boa Nova Tea House and the Serralves Museum of Contemporary Art in his home town of Oporto in Portugal.
Chipperfield said he had encouraged his colleagues to collaborate on designs so as to show that architecture was not just about unique eye-catching projects but more about "something created in collaboration with every citizen."
The British designer also paid homage to the host city saying: "The city shames us by its beauty, reminding us of the real possibilities of architecture, both as individual acts and as part of a greater vision."