This was never an election that promised the possibility of a new era. The 76-year-old president and his defeated rival, Atiku Abubakar, 72, have been around the Nigerian political scene for decades and represent two parties often associated with cronyism and corruption.
Indeed Mr Buhari's victory may in part have to do with public mistrust of his opponent who had to reject allegations of corruption during the campaign.
The president did make some efforts in his first term to counter the graft which has seen tens of billions drain out of the exchequer.
His personal financial integrity has never been questioned. But he has been widely criticised for not going fast or far enough. Will he be more vigorous in his second term?
'Baba Go Slow'
A dose of realism is needed: the breadth and depth of corruption is so great, it affects so many aspects of public life that making serious inroads into the problem would require a focus, energy and application that was lacking in President Buhari's first term.
His absence from the country for long periods due to ill-health - he sought treatment in London for a still undisclosed illness - gave the impression of an administration that often crawled rather than strode.
President Buhari has been lucky in his choice of deputy.
Vice-President Yemi Osinbajo showed himself to be dynamic and brave when he stood in as acting president, notably reining in the security services and acting to stabilise the naira, the local currency, at a time of deep economic uncertainty.
By contrast Mr Buhari has been nicknamed "Baba Go Slow". It took him six months to appoint his cabinet first time around.
Economically, the country remains dependant on oil prices for 70% of government revenues - a long-term vulnerability that helped pull Nigeria into recession between 2016-17.
The World Bank has predicted sluggish economic growth: 2.2% for the coming year in a country with unemployment of more than 20% and nearly half the population living in extreme poverty.
Ending the dependency on oil revenues needs to happen at a much faster pace.
President Buhari also faces an array of security threats from clashes between farmers and herdsmen in the Middle Belt, continuing instability in the oil-producing Niger Delta and - most worrying of all - a revived threat from Islamist extremists in the north of the country.
There, the Boko Haram offshoot - Islamic State West Africa Provice (ISWAP) - used the elections period to stage a series of high-profile attacks including an attempt to fire rockets into the city of Maiduguri on polling day.
For a president at the height of his powers these would be a formidable array of challenges. But Mr Buhari is in his seventies with a history of health problems.
It may be that he is rejuvenated by victory and his second term is more dynamic than the first.
Culled from the BBC.