Former acting PSNI Chief Constable Colin Cramphorn has died.
Mr Cramphorn was Northern Ireland deputy chief constable until 2002
The police officer, who was deputy chief constable of the RUC, had been West Yorkshire's chief constable for the past four years.
He died after a lengthy battle with cancer. Mr Cramphorn, 50 was diagnosed with prostate cancer in 2004.
As RUC deputy chief constable, and then acting PSNI chief constable, he oversaw the introduction of the new policing arrangements for Northern Ireland.
In a statement, the PSNI said: "The contribution by Colin Cramphorn to the history and development of policing in Northern Ireland can never, nor should ever, be understated.
"The successful evolution of the Police Service of Northern Ireland as a professional policing organisation, which is regarded highly both at home and abroad, is in no small measure due to his dedication, drive and unassuming but effective commitment.
It added: "In the highly sensitive and often politically-charged atmosphere which prevailed following the Patten report, he recognised the importance of building on the solid foundations of the past in order to create a new service of which every citizen could, and should, be proud.
"In that he succeeded."
As West Yorkshire's chief constable, Mr Cramphorn led the force during a time when it was rocked by the fatal shootings of two officers - Pc Ian Broadhurst on Boxing Day in 2003 and Pc Sharon Beshenivsky last November.