Pope Benedict XVI has called on the media to underpin its work with ethical considerations and do more to promote the "dignity of the human being".
The pontiff praised the media but said it also posed dangers
The pontiff said there was a need for what he called "info-ethics" - as much as bio-ethics in the fields of medicine and biological research.
He said the media was often used to promote vulgarity and violence and to legitimise "distorted models of life".
But he also said the media helped to spread democracy and promote dialogue.
Correspondents say the Vatican has frequently accused the media of promoting consumerism and lifestyles that it considers unethical, such as pre-marital sex and homosexuality.
'Overstepping the mark'
In his three-page message, the pontiff said: "When communication loses its ethical underpinning and eludes society's control, it ends up no longer taking into account the centrality and inviolable dignity of the human being."
He continued: "While claiming to represent reality, it can tend to legitimise or impose distorted models of personal, family or social life.
"Moreover, in order to attract listeners and increase the size of audiences, it does not hesitate at times to have recourse to vulgarity and violence, and to overstep the mark."
His message was for the Catholic Church's World Communications Day on 4 May.