NSW Police have made a new appeal to find Brisbane woman Kathleen Riethmuller, who went missing in Sydney almost a year ago, as part of Missing Persons Week.
Police suspect the 28-year-old may be alive and possibly living in Melbourne.
Her belongings were found inside a backpack on Centennial Avenue at Lane Cove on Sydney's lower north shore on October 28 - the same day she went missing.
The backpack contained important items, including identification documents and bank cards.
Ms Riethmuller had shopped at Artarmon about 11.40am on October 28 and was sighted again at 2.30pm the same day in North Sydney wearing a long sleeve denim dress and black flat shoes.
NSW Police Minister Paul Toole said officers want to find Ms Riethmuller to ensure she is safe and well.
"The ripple effect that occurs when a person goes missing without reason or without a trace shouldn't be underestimated," Mr Toole said on Monday.
Missing Persons Registry Manager, Detective Chief Inspector Glen Browne, said police need new information to find Ms Riethmuller.
"Her behaviour was clearly out of character when she was last seen, and we've been unable to establish any logical reason for her movements that day and subsequent disappearance," Det Ch Insp Browne said.
"Investigators strongly suspect Kathleen may be alive and possibly living interstate, and any information to that effect would be very helpful to police.
"Ultimately we need the public's help."
Ms Riethmuller is described as being of Caucasian appearance, about 165cm - 175cm tall, of thin build, with long dark hair.