[en] The effectiveness of our nation's deterrent capability is dependent not only on the nuclear weapons we have or can produce, but also on our ability to reliably produce the nuclear materials, including a rare gas known as tritium, needed for those weapons. The Department of Energy is responsible for producing these nuclear materials to meet requirements determined by the Department of Defense. Over the last 40 years, the Department of Energy has built and operated as many as 14 reactors to produce nuclear materials. Today, however, most of those reactors have been shut down, and although the remaining reactors capable of producing nuclear materials, they cannot last indefinitely. This document discusses the technology and the need for new production reactors