National Nuclear Security Administration (NNSA) Office of Nonproliferation Research and Development NA-22 Simulations, Algorithms, and Modeling program that investigates how social modeling can be used to improve proliferation assessment for informing nuclear security, policy, safeguards, design of nuclear systems and research decisions. Social modeling has not previously been used to any significant extent in proliferation studies. This report focuses on the utility of social modeling as applied to the assessment of a State's propensity to develop a nuclear weapons program.During the literature review and preliminary assessment conducted and documented in the first stage of this project (PNNL-18438, Utility of Social Modeling for Proliferation Assessment: Preliminary Assessment), we concluded that there are clearly opportunities to use social models to improve the understanding and assessment of proliferation-related problems particularly State-level proliferation. We discovered that since the advent of nuclear weapons political scientists have theorized about factors that indicate whether a State is pursuing the development of nuclear weapons program. The social factors identified by political scientists include indicators such as national identity, leadership, politics, domestic security, and economic interdependence which complement technical factors such as economic capability, nuclear capability, and availability of fissile material. For the purposes of this research, we refer to these social and geopolitical indicators as -social factors.‖ We assert that social modeling offers a way to leverage this body of theory and analyses to support proliferation assessments.