Pharmacokinetics (PK) and pharmacodynamics (PD) are key concepts in drug discovery and development that describe how a drug moves through the body and its effects on biological systems. PK focuses on the processes of absorption, distribution, metabolism, and excretion (ADME), while PD deals with the relationship between drug concentration and its therapeutic or toxic effects. Understanding these areas helps to optimize drug dosing, predict therapeutic outcomes, and minimize adverse effects. Several Python tools are widely used for modeling and analyzing PK/PD data. This chapter provides an overview of PK/PD analysis using Python tools.