The success of any arms control treaty generally depends on its ability to achieve its primary objectives and intended outcomes. At the heart of measuring such success are effective compliance criteria and verification mechanisms. This includes the ability to apply metrics to assess tangible outcomes and measurable outputs and benchmarks of achievement, including on-site visits. In relation to nuclear issues, this also means that verification of both the non-diversion of nuclear material from declared peaceful activities (i.e., correctness of conduct), and the absence of undeclared or clandestine nuclear activities in a particular state (i.e., completeness in following treaty terms).