In December 1967 the Universal House of Justice wrote to all National Spiritual Assemblies expressing the need of the World Center for letters written by the Guardian to them, or to their subsidiary institutions, as well as to the friends under their jurisdiction.
The Universal House of Justice requests you, therefore, to check again in your archives or files of correspondence with the Guardian for any further letters which have not yet been forwarded to the World Center and to appeal to the believers under your jurisdiction, calling upon those who were privileged to have received letters from the Guardian to send the text of such letters to the World Center.
To assist your National Spiritual Assembly and the friends to carry out this urgent project the following points from the letter of December 1967 from the Universal House of Justice are here repeated for your consideration.
1 Recipients of letters from the Guardian have the inherent right of deciding to keep the letters themselves, or to have them preserved for the future in their families. To assist the Universal House of Justice, however, in its efforts to study and compile the letters of the Guardian, the friends are urged to provide, for dispatch to the Holy Land, photostatic copies of their communications from the Guardian if they wish to keep the originals themselves.
2 If they are not in a position to provide such copies, they should kindly allow National Spiritual Assemblies to undertake this project on our behalf.
3 Should any believer possess letters so personal and confidential that he does not wish to disclose their contents to any institution other than the Universal House of Justice, he is invited to send either the originals or copies of such letters, marked confidential, directly to the Universal House of Justice, by registered mail, with any instructions he wishes to be followed.