Welcome to the wonderful, practical world of fluid analysis utilization. There are plenty of labs around the world processing millions of oil, coolant, and fuel samples every year. Most of them do very professional work, however, the data received from them usually fall into two main categories: 1). The information is incomplete for a machine health assessment, or; 2). At the user’s end, nobody is acting on the information at a level that would allow good, proactive maintenance activity. The sad truth is that very few companies make use of the valuable information contained in fluids. This work, , supports all activity around fluid analysis so managers can lay a more solid foundation for maintenance. It serves as a major contribution to both the science and art of fluid analysis, and is destined to become the cornerstone of every successful condition-based maintenance program. The examples and recommendations will have direct application to implement a true predictive maintenance program. More than 100 examples come from real-life cases, and reflect what many fleet managers encounter in their daily challenges.