What does it mean to be HSG leader? Most importantly, a holistic small group leader must follow Jesus, the Good Shepherd. They must recognize that they serve as under-shepherds of groups usually no larger than 15 members, with 12 being the optimal number. If you feel that you are called to strengthen the weak, heal the sick, bind up the injured, bring back the strays, seek the lost, and lead gently - then becoming a small group leader just might be for you.