Columbia University has overarching policies on leaves of absence ( voluntary, involuntary, medical, military and others types) to which the Mailman School community adheres:

http://facets.columbia.edu/voluntary-leave-absence-policy

http://facets.columbia.edu/involuntary-leave-absence-policy

http://facets.columbia.edu/military-leave-absence-policy

Additional Mailman School Policies:

Doctoral students are required to be continuously registered.  Any interruption in continuous registration must be discussed with the student's academic department and OSA. Through this discussion, one potential option (with department and OSA approval) might be a leave of absence.

Master's students who will not be registering for more than two semesters must apply for a formal Leave of Absence. Leaves are often in order in other circumstances as well.  This can be accomplished by completing the Leave of Absence form available in the OSA and online at:

All students must meet with their department, secure department approval and return the form to OSA. Leave of absence requests are generally approved for two semesters with a maximum of four semesters. Exceptions to the two semester limit will be considered on a case by case basis through a petition to the student’s department and final approval by OSA. Students who are interested in pursuing their degree candidacy after the time limit on approved leaves must reapply to the school.