Here is the official link to the Prince of Wales' correspondence with government officials.
and Clarence House's official statement.
A Clarence House Spokesperson said:
'The correspondence published by the Government today [Wednesday 13th May 2015] shows the range of The Prince of Wales' concerns and interests for this country and the wider world. The twenty-seven letters (ten from His Royal Highness, fourteen from Ministers and three from Private Secretaries) were written between September 2004 and March 2005.
'The Prince of Wales cares deeply about this country, and tries to use his unique position to help others. He has devoted most of his working life to helping individuals and organisations, to make a difference for the better of this country and the world.
'Over the past 40 years in his role as Heir to The Throne, The Prince of Wales has visited countless places and met numerous people from every walk of life. He carries out over 600 engagements a year. This gives him a unique perspective, which has often led to him identifying issues which he believes he, or his charities, or his other connections, can help address. Sometimes this leads him to communicate his experience or, indeed, his concerns or suggestions to Ministers, from all Governments, of whatever party, either in meetings or in writing. Government Ministers have often encouraged him to do so, and many have welcomed The Prince’s views and ideas on a range of subjects. There are examples of this in the correspondence that has been made public.
'The letters published by the Government show The Prince of Wales expressing concern about issues that he has raised in public like the state of farming, the preservation and regeneration of historic buildings, the re-use of disused hospital buildings, the professional development of schoolteachers, and others. In all these cases, The Prince of Wales is raising issues of public concern, and trying to find practical ways to address the issues.
'Nonetheless, The Prince of Wales believes, as have successive Governments, that he should have a right to communicate privately. The publication of private letters can only inhibit his ability to express the concerns and suggestions which have been put to him in the course of his travels and meetings. This view has been given effect by Parliament, which passed legislation in 2010 to ensure that the communications of The Prince of Wales, and that of The Queen, should be exempt from publication under the Freedom of Information Act. This change emphasised the unique constitutional positions of the Sovereign and the Heir to the Throne. Clarence House continues to believe in the principle of privacy.'