No special expertise is required. Instead, the question is turned back to the group for exploration and discussion. Since the communication skills in these workshops apply to people of all ages and all caring relationships, any parent with a child of any age can benefit. However, parents usually feel more comfortable being in a group with other parents whose children are in a similar age group experiencing similar issues and problems. Although books are given to each parent, those who can't read, learn by listening.
Cartoons provide visual reinforcement.
Role play practice lets people learn by doing. The audio tapes have universal applicability because they minimize cultural, religious or socioeconomic status indicators. They incorporate both male and female examples. I've run groups successfully for mothers. Obviously you need to start by scheduling the course at a time when most fathers are available-usually evenings or weekends.