Clarence woman Melissa Ewings (31) has not been seen since Sunday.
She was reported missing when she did not turn up to work yesterday and there are fears for her safety.
Police say Ms Ewings told a friend on Sunday afternoon she was going for a walk to the Clarence River, near Kaikōura
Police are urgently seeking information on her whereabouts, as her friends and family have serious concerns for her welfare, the spokesperson said.