This book constitutes the proceedings of the 11th International Conference on Security and Cryptography for Networks, SCN 2018, held in Amalfi, Italy, in September 2018.<p>The 30 papers presented in this volume were carefully reviewed and selected from 66 submissions. They are organized in topical sections on signatures and watermarking; composability; encryption; multiparty computation; anonymity and zero knowledge; secret sharing and oblivious transfer; lattices and post quantum cryptography; obfuscation; two-party computation; and protocols.</p>