The booklet, Called to a Noble Adventure - prepared by the Catholic Youth Ministry Federation (CYMFed) for the Bishops' Conference of England and Wales - explains that only a small proportion of young people who say they are Catholic "attempt to live by the beliefs and practices that they say are important".
Many, it said, are "happy to hold different beliefs side-by-side with no apparent tension arising from the contradictions."
"Today, from the perspective of many young Catholics, there is simply no single way of how they identify with and live out their faith."