This volume contains the proceedings of EXPRESS/SOS 2023: the Combined 30th International Workshop on Expressiveness in Concurrency and the 20th Workshop on Structural Operational Semantics, which was held in Antwerp, Belgium, as an affiliated workshop of CONCUR 2023, the 34rd International Conference on Concurrency Theory. The EXPRESS/SOS workshop series aims at bringing together researchers interested in the formal semantics of systems and programming concepts, and in the expressiveness of computational models.

翻译：本卷收录了EXPRESS/SOS 2023：第30届并发表达能力国际研讨会与第20届结构操作语义研讨会联合会议的论文集。该会议作为第34届并发理论国际会议（CONCUR 2023）的附属研讨会，于比利时安特卫普举行。EXPRESS/SOS系列研讨会旨在汇聚对系统和编程概念的形式语义学以及计算模型表达能力感兴趣的研究人员。