Church Community Builder is a discipleship-focused ChMS that includes multiple areas of ministry including group functionality for small groups, ministry teams, etc. Groups have the option for discussions in a closed environment but allows church members to participate in the conversations directly from their email (without logging in).
Church Community Builder works to help churches reduce the number of separate ministry tools that their ministry is using so that group activities are not separate from the bigger picture of shepherding and discipleship in the church.
If you want to chat more about CCB, let me know. I'll get you connected with someone from our team.