This document provides explanations for a database on the selectivity of pesticides from the International Organisation for Biological and Integrated Control of Noxious Animals and Plants (IOBC). The database contains toxicity classifications for pesticides against beneficial arthropods, bees, earthworms, and fish based on test results. The classifications range from harmless to highly harmful. The document describes the sources and methodology used to compile the database, including the criteria used to determine toxicity classifications. It is intended to help users select pesticides while considering effects on non-target organisms.