The textbook is essential for medical students and can serve as a reference for young doctors in postgraduate training. It covers all major topics of clinical biochemistry: from preanalytical issues, acid-base balance and ion dysbalances, via special topics (diabetes mellitus, gastrointestinal tract or laboratory investigation of important organs - liver, kidney, heart) to therapeutic drugs monitoring and trends in laboratory medicine. Authors are leading experts in clinical biochemistry. The topics are presented in readable and comprehensive form and are suplemented by intractive e-learning course with control quizzes.