Privacy Commissioner Marie Shroff is urging anyone who mistakenly receives another person's private information to immediately return it to the sender.
Her comments come on the heels of another major privacy blunder, involving a Katikati man and two other men from out of this region whose legal aid details were incorrectly sent to a Tauranga mother.
Ms Shroff said all agencies were required to take reasonable steps to protect the security of personal information and to avoid unintended leaks or disclosure.
"I encourage people if they find that they have received personal information about someone else to return it to the sender or, in some instances, to return it to our office.
"It's simply a case of 'do what you would want someone else to do' if it was your information out there," Ms Shroff said.
The breach, one of a a number involving multiple government entities recently, was revealed in yesterday's edition of the Bay of Plenty Times.
The documents were sent by the Ministry of Justice's Legal Aid Office in Rotorua.
The shocked 39-year-old Katikati man at the centre of the blunder said he would be taking legal advice but could not be contacted for further comment last night.
The Tauranga mother said last night that she would be posting the Katikati man's letter back to him and would forward the other two letters to the men's Porirua-based lawyer.