How can you tell if a missionary candidate is prepared for effectiveness on the field? How can you evaluate a field missionary? What are the most important markers of effectiveness? Propempo submits this series to help the discussion. 13 keys will be examined, one each week. We'll try to define each one, show which shortcoming each may address, and suggest some remedies to build the qualities that are the keys. Our goal is to avoid preventable attrition and prepare effective field missionaries for the glory of God.