EMS

From the website:

We are a professional society with more than 350 members comprised of missiologists, mission administrators, teachers, pastors with strategic missiological interests, and students of missiology.

The Evangelical Missiological Society (EMS) exists to advance the cause of world evangelization. We do this through study and evaluation of mission concepts and strategies from a biblical perspective with a view to commending sound mission theory and practice to churches, mission agencies, and schools of missionary training around the world.  We hold an annual National Conference and eight regional meetings held throughout the USA and Canada.