In 2017, the Church of England asked Church Army’s Research Unit to find out about successful, unsuccessful, and unproven mission with young adults (aged 18 to 30) which has taken place within the Church of England, other denominations, or through para-church groups.
In researching this topic, they completed 12 case studies of different approaches to mission and evangelism with non-churched young adults. At their website you can find more information about each case study. Encouragingly a key theme that emerged from many of the churches they visited was: reaching and engaging with 18-30-year-olds may not be as difficult as you think.
You can read the main findings in this report.