Database Systems are integral components of Computerized Information Systems employed in Social, Economic, Health and Industrial sectors in our Society. Their importance cannot be overemphasized. Accordingly, Database Management Systems has remained a vital area for many decades in the training and education of Computer Scientists, Information Technology experts, Software engineers, Data scientists, to mention a few. Fundamentals of Modern Database Systems is carefully structured to cover the vital elements in Database Management Systems Curriculum especially for Undergraduate Degree and Diploma programmes. Data/Database Administrators and Scientists will also find the text invaluable. The content is practice-oriented and reflects succinct details using vivid examples and illustrations intended to enable the reader decipher every section of it. The book is handy comprising thirteen (13) chapters covering such vital areas as Data models, Relational Algebra and Calculus, StructuredQuery language, Database planning, Design, Implementation, Database security, Data warehousing, and NoSQL Databases. It could also be used as a reference guide in Classes, Laboratories and ICT Units.