Both Zaha Hadid and Will Alsop started this way, while Brisac Gonzalez, a London-based duo barely out of their 30s, have just completed the £26m Museum of World Culture in Gothenburg following an anonymous contest.
Others may decide to cut their teeth on housing - designing homes for friends, family or themselves. Richard Rogers' first project was a house for the parents of his first wife in Cornwall, and more recently, the three partners of Buckley Gray Yeoman kick-started their company by constructing or converting their own places.
And then there are young architects who try both routes. Three residences, in Dublin, Tokyo and Antiparos, Greece, were recently honoured by the AR&D Awards for Emerging Architecture, a competition launched in 1998 as a way to recognise architects under the age of 45 (relative whipper-snappers in the field). Each year, award judges sift through hundreds of entries to find five award winners, three high commendations and 11 commended schemes.
Each of the homes named this year is the first project, or one of the first, for its architect. But they will certainly not be the last, according to Peter Davey, chairman of the AR&D judges and editor of Architectural Review. David McDowell created Wheatfield Courtyard in County Dublin by converting decayed old farm buildings into a modern home for his family. "Rather than perhaps taking the traditional route of competitions or of waiting for small commissions to come along, I looked at the alternative approach of generating my own opportunities," he explains.
The idea behind Wheatfield Courtyard was to reuse a traditional agricultural farmyard through restoration, demolition and new construction. The existing buildings, which were set at right angles to each other, are now linked by a glass, cedar and a galvanised steel box. Another box projects westward, giving the living room views of the surrounding countryside.
Davey describes the project as a welcome change from the current crop of smug villa developments and bungalows popping up around Ireland's prosperous countryside. For McDowell, it's both a home and starting block. He worked at London's Nicholas Grimshaw & Partners before returning to Dublin, but says that, like many young architects in Ireland, he thought a residential project would be a good way to launch his own practice.
Homes are a common first step in Greece, too, according to AR&D honoree Alexandros Vaitsos, although young Greek architects get more opportunities to work on new structures (as opposed to conversions or extensions). His Krater House, on the island of Antiparos, was commissioned by a local developer who happened to be a personal friend of the team at his firm, Deca Architecture.
It sits on a hill, dug into the side, forming a mythical crater protected from Meltemi - the Aegean's prevailing north-east summer wind - by a three-storey tower. To the south is a separate, white, rectangular building that houses the kitchen, dining room and communal areas. On the west side is a narrow 25 metre-long swimming pool that hovers over the slope.
Deca's developer client was building half a dozen holiday homes on Antiparos, but liked Vaitsos's design so much that he kept it for himself. The AR&D jury commended Krater House because of the care with which it has been carved into the landscape. It was three-year-old Deca's first completed project.
But the residential project that took top honours at the AR&D awards was The Cell Brick House in Tokyo by Atelier Tekuto. The home was built to fit on to a tiny corner site in a tranquil suburb for a designer and her 20-something son and daughter. It is four storeys of boxes and squares - a cunning ensemble amounting to only 85 sq m. The outer steel skin is coated with a fused ceramic material developed by Nasa that is supposed to have almost miraculous properties of heat resistance and transmission.
AR&D's sceptical judges did recognise the home's practical limitations, Davey says. "Clearly, a house made in this way would not suit everyone. It raises numerous questions about privacy, both aural and visual." But they couldn't help honouring the architect for his youthful exuberance, sense of adventure and ingenuity.