Police are offering $50,000 for information relating to the disappearance of a Tauranga woman 27 years ago.
Ms Williams was last seen at her home in Munro Street on the evening of 5 June 1986. She was 25 when she went missing and her disappearance is being treated as a homicide.
Detective Inspector Mark Loper said on Wednesday that a review of the case began 18 months ago and as a result new information has taken the investigation in a different direction.
In 1994, police reviewed her disappearance and offered a $20,000 reward for information.
Mr Loper said that over time allegiances and associations change, and police have a number of persons of interest.
Ms Williams' sisters, Melanie and Jacqueline Williams, say events since 1986 have had a crazy and stressful impact on their family and it is sad their father died without a resolution of the case.
They say knowing the case was never closed has helped and they always hope that someone will have answers.
Police say the $50,000 reward will be paid for material information or evidence which establishes the location of Luana Williams or leads to a conviction for her disappearance or death.