Bernard Hogan-Howe has been named by Home Office as the new commissioner of the Metropolitan police.
The former acting deputy commissioner of Britain's biggest police force and chief constable of Merseyside police, said he aims to make “criminals fear the police” as he accepted the post on Monday.
Hogan-Howe was appointed deputy leader of the Met in the wake of the phone hacking scandal.
He stepped into the role vacated by Tim Godwin, who became acting commissioner following the resignation of Sir Paul Stephenson in July.
Hogan-Howe had previously applied for the job in 2009 but was unsuccessful.
Kit Malthouse, Chair of the Metropolitan Police Authority Hogan-Howe had proved himself to be a "valiant and focused crime fighter and we look forward to him bringing his undoubted sense of purpose to London.
“The MPA were impressed by his clear vision, firm resolve and eagerness to get about his task. He was one amongst a distinguished and highly accomplished field and his success is therefore all the more impressive.
Home Secretary Theresa May said the new Met chief "impressed us all with his vision for the Metropolitan Police, his commitment to cutting crime and the important work he has done for the public.
"The government's reforms are transforming the police in this country and Bernard Hogan-Howe has the skills and experience needed to ensure the nation's biggest force is at the forefront of this change.
The other candidates for the top job were acting Met commissioner Tim Godwin, current Association of Chief Police Officers (Acpo) chief Sir Hugh Orde and Strathclyde police chief constable Stephen House.
The candidates were interviewed by home secretary Theresa May, London Mayor Boris Johnson and the Metropolitan Police Authority (MPA).