Roy Jenkins' guest this week is a preacher who's been described as 'one of the world's most effective and compelling spiritual communicators.' Thirty million people are reckoned to have attended his meetings in 75 countries. He's published nearly 50 books. His radio programmes are heard around the world. And this week, the Argentinian-born evangelist Luis Palau is in Wales. He's here to share some of his insights with church leaders, and, at 83, to support Higher, described as 'the largest youth mission to the UK for a generation' with high energy concerts and a range of community events aimed at young people who are seen as 'the hardest to reach'. Recorded ahead of his visit to Cardiff, he shares his views on the challenges facing young people today; his impressive ministry, and how he feels the churches can revitalise their approach to sharing their faith.