Rethinking SLIC* is a research project that aims to develop a legal framework, based on theory and practice, for determining the outer limits of secondary liability for international crimes and serious human rights violations. Questions of secondary liability arise when a person, company, or State is complicit in the commission of unlawful acts. The perpetration of international crimes and serious human rights violations often depends on a wide network of supporting actors, which escape liability because of shortcomings in the law. As such, establishing an improved framework for secondary liability is a pressing issue, particularly in the current era of globalisation where assistance for such acts transcends national borders and when the ultimate harm is particularly grave, as is the case with mass atrocities. Rethinking SLIC* focuses on secondary liability in three areas of law: tort law, criminal law, and State responsibility.