Epidemiology is fundamental to public health, providing the tools required to detect and quantify health problems and identify and evaluate solutions. Essential Epidemiology is a clear, engaging and methodological introduction to the subject. Now in its fifth edition, the text has been thoroughly updated. Its trademark clear and consistent pedagogical structure makes challenging topics accessible, while the local and international examples, including from the COVID-19 pandemic, encourage students to apply theory to real-world cases. Statistical analysis is explained simply, with more challenging concepts presented in optional advanced boxes.