Why do we say “Dress for the job you want”?

This bit of office wisdom took off in the 1970s. John T. Molloy’s 1975 book Dress for Success helped launch the craze for “power dressing” at work. By 1976 career advisers were repeating “dress for the job you want,” and Molloy’s 1977 book for women spelled out the full rule: dress for the job you want, not the job you have.