How much does it cost to join a community in addition to the ones that come with my membership? KB Admin, ATD Updated October 14, 2016 19:23 Follow All ATD Professional members are able to select four communities. To join additional communities, there is a fee of $30 per community per membership year. ATD Professional Plus members have unlimited access to all of the communities’ content. Related articles How many ATD communities of practice are there? How much does it cost to become a member? What are the different session types offered? How do I participate in the ATD communities of practice? Do I have to be an ATD member to join a community of practice?