Mr Liddell - one of New Zealand's most accomplished businessmen - has been announced as an assistant to the President and director of strategic initiatives.
The 58-year-old will lead new White House Strategic Development Group - dubbed the "White House think tank" - which has been tasked with bringing Trump's big picture transformative change items to fruition. He will also interface with private sector forums.
His appointment was announced along with that of Reed Cordish, who is an Assistant to the President for Intragovernmental and Technology Initiatives.
"Chris Liddell and Reed Cordish have led large, complex companies in the private sector, and have played instrumental roles throughout the transition," said President-elect Trump.
"Their skill sets are exactly what is needed to effect substantial change, including system wide improvement to the performance of the government. I am delighted that they will be part of my executive team."
"It is an honor to take on this role for the President-elect and the country," Mr Liddell said.
The announcement comes just days ahead of Trump's inauguration as the 45th president of the United States and at a time when the American public is looking to the president-elect and his Administration to put the polarizing campaign behind them and get down to business.
Mr Liddell - who served as executive director of transition planning for Mitt Romney's 2012 Presidential campaign - joins the Trump Administration armed with huge experience preparing the prior Republican candidate.
A book he co-authored after the 2012 election - Romney Readiness Project: Retrospective and Lessons Learned - has been taken as a bible for presidential transition planning.
During the transition period, Mr Liddell has been the Special Adviser on Presidential Appointments.
He joins other key players as Assistants to the President including chief strategist Stephen K. Bannon. Trump son-in-law Jared Kushner, and White House Chief of Staff Reince Priebus, National Security Adviser Michael Flynn, Director of the National Trade Policy Council Peter Navarro, Director of the National Economic Council Gary Cohn, and, Homeland Security and Counterterrorism Adviser Thomas Bossert.
Mr Liddell has a distinguished international business career spanning roles as chief financial officer from companies ranging from General Motors, to Microsoft and International Paper, and counts helping engineer one of the biggest sharemarket listings in history -- the US$23 billion float of General Motors, as a career highlight.
In 2014 he became CFO of US talent agency WME/IMG, which went onto buy the Miss Universe Organisation - the owner of pageants including Miss Universe and Miss USA - from then US presidential hopeful Donald Trump.
In a television interview late last year, Mr Liddell said he expected people would see a more moderate Donald Trump presidency "than the one seen on the campaign trail."
"People focus on the president, as they should, because the president's the single most important person, but the president works through these huge numbers of other people running various departments and so forth, so who he starts to surround himself, how he manages those people, will define his success."
He is now in a position to help define Trump's success. As he told TVNZ's Q&A programme: "Donald Trump's a very atypical president. He's not a traditional Republican. He's not a traditional Democrat. He's a mixture of both of them.
"And if you want to take an optimistic view, and I'm optimistic, I think he will actually come up with some policies that both sides will be willing to look at."
