I have written several articles in the past few months about missionary work, in the wake of the change in age requirements to serve an LDS mission.
The January issue of the Ensign and Liahona magazines have published two great articles about missionary work:
“Young Women and the Mission Decision,” shows how several adult women applied prophetic counsel regarding full-time missionary service.
“What Mission Would be Best?” provides a table to help senior missionaries see the opportunities available to them.