Military Technical Institute (Serbian: Војнотехнички институт, romanized: Vojnotehnički institut; abbr. VTI) is a Serbian weapons and aircraft design institute, headquartered in Belgrade, and governed by the Serbian Ministry of Defence. It is a top-level military scientific research institution in Serbia, dealing with research and development (R&D) of new weaponry and military equipment as well as with upgrade of the inventory for both branches of the Serbian Armed Forces: Army (including River Flotilla) and Air Force and Defence.