The long serving administrator honed his skills while serving at the Bretton Woods institution before returning to serve at the Treasury.
A communication officer who served with Kinyua when he was Permanent Secretary at Treasury with Uhuru Kenyatta as the Minister for Finance describes him as a professional civil servant.
For nearly a decade, Kinyua served as the PS in the Treasury, and was a central figure in the execution of most economic policies in President Mwai Kibaki's government.
He led the team that crafted the annual Budget, the Treasury's most important policy document that guides government on resourcing and funding.
"He was always very punctual and ensured that work was done to perfection. That is how Uhuru became fond of him and later appointed him Chief of Staff at State House," he says.
Kinyua has also been described as a workaholic, incorruptible and frugal person who liked simplicity and surrendered his government vehicles on Fridays to use his private cars on weekends.
But critics argue that Uhuru was wrong to hire Kinyua because the office required a person who could juggle working with politicians and professionals.
Prof Peter Kagwanja of the Africa Policy Institute claims Kinyua, 70, largely surrounded himself with old friends he had worked with at the IMF and World Bank.
"These were old civil bureaucracy survivors who could not make a difference to his office and that of the president," says Kagwanja.
There are those that argue his aversion to politics saw government viewed as a company which should be managed professionally without too much politicking.
Kagwanja disagrees with that notion arguing that government is a political institution because it is the one that decides how power is divided by interested parties.
Kinyua occupied the office that had earlier been graced by towering luminaries like Simeon Nyachae, Hezekiah Oyugi, Prof Philip Mbithi, Francis Muthaura and Joseph Kimemia.
Dabbled in politics
Most of those people had vast experience in administration and had dealt with politicians in public service before they were appointed.
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Although the likes of Muthaura were professional, they dabbled in politics behind the scenes and ensured that President Kibaki's government was working smoothly.
Those that worked with Kinyua at State House describe him as a soft-spoken economist even in his relationship with staff and senior civil servants.
"He managed his communication very well and dealt with civil servants well while exerting his influence but it is the president who handled the politics," says a senior officer who worked at State House.
Kinyua was appointed Chief of Staff in late 2013, after his predecessor PS Mutea Iringo and Nancy Gitau were pushed out.
Opposition leaders led by the then ODM chair John Mbadi rejected the appointment terming it unconstitutional and calling for his vetting like other civil servants. The then leader of majority Aden Duale insisted that Kinyua's appointment was legal, leading to a stand-off in Parliament.
The back and forth between the lawmakers and the Majority Leader made then Deputy Speaker Joyce Laboso order that the Justice and Legal Affairs Committee investigate the matter.
The opposition MPs argued that while the president had the power to set up new offices based on the advice of the Public Service Commission, the holder of that office should have been picked in a transparent and competitive process.
They further claimed that there was a potential of overlap in Kinyua's job and that of Secretary to the Cabinet Francis Kimemia whose office had been split to create room for Kinyua. The storm, however died down and Kinyua assumed his role and continued serving until he signed off this week.
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