Visas are typically valid for 3 months and allow for a single entry with a duration of stay not to exceed 30 days.
The 6 month multiple entry visa typically allows for stays of up to 90 days per entry.
The one year multiple entry visa allows for stays of up to 90 days or 180 days maximum per entry. This visa is only issued to those who can show a history of frequent travel to Qatar (for example have previously been issued a visas). It is issued solely at the discretion of the Embassy of Qatar.