Chapter 3 further expands on systemic effect and argues that impact of the Rome Statute on domestic legal systems is better described as “internalization.” Internalization is the process whereby states demonstrate compliance with international law. The chapter examines internalization in Afghanistan, Colombia, Libya, and Uganda. Indicators of systemic effect, in the form of internalization, include implementation of domestic laws covering the Rome Statute crimes; the establishment of new or specialized investigative units or chambers to investigate or prosecute Rome Statute crime; or (genuine) national proceedings for Rome Statute crimes. The chapter concludes that “internalization” is taking place in all the countries under study. Laws have been amended, and new institutions established. National proceedings took place in all four countries. However, domestic proceedings in Colombia and Uganda demonstrate that it can be complex to assess for “genuineness.” In fact, most domestic proceedings are taking place in Colombia, a country with a robust legal system. This may mean that the Court has the most impact where it is needed the least.