The inquest into the death of Inishowen pensioner Maura Porter has started at Buncrana Courthouse.
The 70-year-old mother-of-two died from injuries she sustained in a road traffic accident near her home in Carndonagh on December 30th, 2013.
It is alleged that an ambulance took 50 minutes to reach Mrs Porter on the evening.
Mrs Porter died six hours later at Altnagelvin Hospital in Derry.
The director of the National Ambulance Service, Mr Cathal O’Donnell is among a number of witnesses due to give evidence.
Others include Mrs Porter’s husband Neil, the driver of the car involved in the accident Austin Stewart and Garda witnesses.
The inquest is being conducted by coroner for Donegal, Dr Denis McCauley.