Horne began his career in journalism and worked for a number of
Frank Packer's publications, first as a journalist for
The Telegraph, then editor of the magazine
Weekend, and later the fortnightly intellectual periodical
The Observer (1958–61). As editor of the flagship magazine
The Bulletin (1961–62 and 1967–72), he removed the magazine's long standing motto "Australia for the White Man". He was co-editor of
Quadrant magazine (1964–66). He also worked on writing, arts and citizenship boards and was an executive member of the Australian Constitutional Commission. ==Honours and legacy==