Navy Aegis Ballistic Missile Defense (BMD) Program: Background and Issues for Congress [August 4, 2015] [open pdf - 710KB]
"The Aegis ballistic missile defense (BMD) program, which is carried out by the Missile Defense Agency (MDA) and the Navy, gives Navy Aegis cruisers and destroyers a capability for conducting BMD operations. Under MDA and Navy plans, the number of BMD-capable Navy Aegis ships is scheduled to grow from 33 at the end of FY2015 to 48 at the end of FY2020. The figure for FY2020 may include up to four BMD-capable Aegis cruisers in reduced operating status as part of a program to modernize 11 existing Aegis cruisers. Under the Administration's European Phased Adaptive Approach (EPAA) for European BMD operations, BMD-capable Aegis ships are operating in European waters to defend Europe from potential ballistic missile attacks from countries such as Iran. BMD-capable Aegis ships also operate in the Western Pacific and the Persian Gulf to provide regional defense against potential ballistic missile attacks from countries such as North Korea and Iran."
CRS Report for Congress, RL33745
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html