This week, all being well, he will experience one of his finest hours, as host to the heads of the world's seven richest nations in the annual summit of the Group of Seven industrialised countries.
Not an overtly proud or arrogant man, Mr Barre will bask unashamedly in the glory of the occasion and plans to show off his magnificent 19th century town hall to the full. Washing and brushing have been the very least of what has been done in preparation. A week ago, there was still sheeting and cables all over the floors; you shared the lifts with trestles and paintpots, and the smell of varnish was everywhere.
Thursday night's opening G7 dinner, with a secret menu that will boast the quintessence of Lyons' renowned cuisine, is to be held - weather permitting - in the loggia courtyard. The three day event will be wound up with a sound and light show over the Rhone for the citizens of Lyons, to compensate them for the inconvenience of having their city taken over by the security requirements of seven international leaders.
When you meet Mr Barre, it is evident that, one year into his mayordom, he is having a whale of a time. A former university economics professor, who has moved easily between the academic and political worlds for the best part of 40 years, he is best known for serving as Valery Giscard d'Estaing's prime minister from 1976-81.
But he has weathered the decades better than Giscard, and so have his politics. His statements are still closely watched and widely respected. He manages to combine a free-market pro-European stance with a practical social conscience - a combination that is increasingly being accepted by governments across Europe.
Mr Barre is small and his round face and smile give a general impression of rotundity - but he is actually quite dapper, despite his reputation as a bon viveur. He has the directness and spontaneity of someone who is at ease with himself and his authority.
Just over a year ago, Mr Barre thought he had made his exit from French politics by declining to stand for the presidency. He said at the time and still says that the only purpose of having power is to achieve objectives, and he judged that "the political and social conditions would not have allowed me to pursue the policies of reform and change that I thought necessary for the French economy". Almost as an afterthought, he adds: "And you know, I don't regret it one bit."
So why, given the standing and influence he enjoys, not just in France but in Europe, has he returned to frontline politics by standing for the post of city mayor - albeit of a city which is the second largest in France and which prides itself on having been the capital of Roman Gaul? "I didn't really stand at all," he corrects my terminology. "A deputation of local MPs and councillors approached me and asked me whether I would head their list for the council elections. In fact, I had quite other plans."
Mr Barre was approached as someone who had been the local MP since the late Seventies and chairman of the regional council since the mid-Eighties. But their main consideration - and the reason Mr Barre agreed to their request - was the political mess in which the city of Lyons then found itself.
The high-flying incumbent mayor, Michel Noir, had just been convicted of corruption, and Lyons had some of France's toughest housing estates and social problems on its periphery which were on the brink of exploding. If the political right was to retain power and the reputation of Lyons was to be rescued, the right's candidate for mayor had to be someone who enjoyed respect, if possible, nationally and across parties.
Mr Barre's list won a first-round victory. His original plan - it transpired when I posed this "indiscreet" question - had been to retire. Now, he has another three and a half years of political struggle ahead. Mr Barre, however, seems to regard it as a gentle and rather pleasurable form of combat - until you see him in the council chamber. Here, he rules with a rod of iron and some tart repartee. When a National Front councillor objected to the choice of music for the sound and light show as "too international" (with Bob Dylan), the mayor snapped back: "So what do you call Debussy, then?"
With the G7 summit on his doorstep (a gift from Jacques Chirac after he became president), he wants Lyons - a city regarded in France as inward- looking and hidebound despite its mercantile history - to promote itself to the outside world. "But that depends on the Lyonnais continuing the impetus," he says, adding, as though this sounds too negative. "And I believe they will."
t More than 5,000 people marched through Lyons on Saturday to protest about the holding of the G7 summit in the city and to demand that "other voices" be heard. The marchers represented trade unions, groups campaigning against unemployment, racism, environmental pollution, Third World indebtedness and a host of other ills. The march was led by the dissident bishop and gay rights campaigner Jacques Gaillot, flanked by actors singing "When will the revolution come?"