James Rothfield was last seen at Hornsby, Sydney on 12 August 1996. He was seen to be walking around the Hornsby area at the time. He failed to attend a scheduled appointment at 10.00am that day. James had no identification on him and it is unknown whether he had any money on him either. It is unknown where James is likely to frequent. James has left behind his personal belongings, including his wallet. James was last seen wearing a white shirt and green track suit pants. He suffers from a mental illness but is not a violent person. He left the premises undetected and without money or personal effects. There are grave concerns for his safety.

This year's Missing Persons Week is focusing on the number of people in the community with mental illness who have become separated from their families.

James Rothfield went missing from Hornsby Hospital around 10am on July 12, 1996 while being treated for schizophrenia.

His mother Diana Rothfield believes he left because he was going to be put in an institution by authorities.

"I think he's alive," Mrs Rothfield said. "I think he has lost his memory, he doesn't know about his past, I just don't think he is dead."

An official inquest was held into Mr Rothfield's disappearance and the family members were offered a death certificate, which his mother refused.

"I just don't believe he's dead and neither does his  brother."

In recent years, James's father Dr David Rothfield has died and his brother Andrew has had three children.

"It is very, very, sad. We are a close family and James was very close to his father."

"He had cancer and it was very hard for him. This whole experience has changed our lives ."

Ku-ring-gai detective Sergeant Peter Feuerstein has investigated many sightings over the years but none were ever confirmed.

"It is one of the longest missing persons case we've had at this command and it would be nice to see it resolved," Sgt Feuerstein said.

"His family have always been desperate to find him."

"They are such a lovely family; his mother always wanted some resolution, some closure.

"You can never give up hope but it is so traumatic not to have any answers.

"The family have never stopped seeking answers."

Mrs Rothfield cannot legally leave anything to James in her will and would at least like that resolved.

"We love you, James, please come home".

James Rothfield would be aged 47. He is 178cm tall with brown hair and eyes.

Anyone with information about him should phone Hornsby police on 9476 9799.