This document discusses the principles behind ISO/IEC 17025 and how understanding these principles can benefit laboratories and assessors. It provides a brief history of ISO/IEC 17025 and describes the eight key principles that underlie its requirements: capacity, exercise of responsibility, scientific method, objectivity of results, impartiality of conduct, traceability of measurement, repeatability of test, and transparency of process. Understanding these principles helps provide context for why specific requirements exist and gives assessors and laboratories a framework for ensuring technical competence.