This essay analyzes the outcome of the seventieth session of the U.N. International Law Commission held in the summer of 2018 in New York and Geneva. Notably, the Commission completed on second reading two topics: subsequent agreements and subsequent practice in relation to the interpretation of treaties; and identification of customary international law. The Commission completed on first reading two further topics: protection of the atmosphere; and provisional application of treaties. Progress was also made in developing draft conclusions on peremptory norms of general international law (jus cogens), draft principles on protection of the environment in relation to armed conflict, and draft articles on succession of states in respect of state responsibility. The Commission commenced a debate but otherwise did not make progress with respect to its topic on the immunity of state officials from foreign criminal jurisdiction. The Commission, however, added a new topic to its agenda on general principles of law, and added two new topics to its long-term work program, namely on universal criminal jurisdiction and sea-level rise in relation to international law. The Commission did not work on a topic that completed its first reading in 2017 and that, after receiving reactions from governments and others, will likely undergo its second reading in 2019: crimes against humanity.