Gastroenterology is a cutting-edge specialty that includes both common diseases and syndromes affecting the majority of the population as well as rare specialized pathological entities concerning very specific groups of patients. The range of diagnostic and therapeutic approaches within the specialty is vast, extending from detailed history taking to the management of patients before and after liver transplantation and from simple diagnostic to the most complex therapeutic endoscopies. 

At the same time, in many gastroenterological diseases, rapid progress is occasionally observed in the understanding of pathophysiological mechanisms, the natural course of the disease, and diagnostic approaches, culminating in the emergence of new therapeutic agents and interventions.

Based on the above, it is obvious that a Gastroenterology textbook cannot fully cover all diagnostic and therapeutic fields nor provide the gastroenterologist with all the knowledge required for the modern practice of the specialty. However, it can include the core body of information that constitutes the evidence-based knowledge and is not significantly revised over time. Thus, it becomes a solid foundation for building and integrating all new data arising from ongoing medical education, attendance at scientific events, and literature review.

The present textbook, "Modern Gastroenterology," is the first comprehensive Greek Gastroenterology book and aims primarily to cover, with a relatively uniform structure, the basic knowledge of the most common and frequent diseases and syndromes of the digestive tract, liver, biliary system, and pancreas. To achieve this goal, each chapter presents all the essential points at the beginning, followed by evidence-based views on the topic, enriched with numerous tables, diagrams, and images. The book's content is mainly intended for medical students and resident physicians but also for any junior or senior specialist colleague interested in updating their fundamental knowledge of the diseases and syndromes of the specialty.

All authors, mainly Gastroenterologists and members of the Teaching and Research Staff (TRS) of the country's Medical Schools, as well as selected Directors of the National Health System in close collaboration with our Clinic, responded willingly and within a reasonable timeframe to the writing of the chapters assigned to them. Thus, the textbook is being published just one year after the decision to publish it. All TRS members of our Clinic, Professors I. Vlahogiannakos, G. Karamanolis, and S. Manolakopoulos, significantly contributed to the initial homogenization of the chapter contents, being responsible for editing parts of the textbook.

In closing this preface, I would like to express my warm thanks to all those who worked and dedicated part of their valuable time to the publication of this textbook: the authors for the chapters they prepared, the TRS members of our Clinic for their assistance in editing the publication, the Clinic's secretary for impeccable administrative support, and the publishing house for the prompt, effective, and high-quality publication of the textbook.

We hope the textbook will meet the expectations of our students, residents, and specialist gastroenterologist colleagues, as well as all colleagues interested in diseases of the gastrointestinal system.