This Special Issue focuses on the integration of artificial intelligence (AI) and machine learning (ML) algorithms into knowledge and data engineering, with a focus on the practical and theoretical advancements that can aid in the resolution of real-world problems. The scope of this Special Issue includes, but is not limited to, knowledge representation and reasoning, knowledge graph construction and analysis, data and knowledge integration, knowledge discovery and data mining, data privacy and security, semantic web and linked data, natural language processing, recommendation systems, decision support systems, and big data processing and analysis. Submissions are invited from both academia and industry, and accepted papers will be published continuously in the journal.