Before the proper lubricant selection can be made, the tribological system must be identified to its fullest extent. This system includes the type of motion, speeds, temperatures, loads and the environment that is specific to the application. Once these parameters are identified, lubrication engineers or tribo-engineers can use their knowledge of the different lubricant chemistries to make a lubricant selection that will optimize the performance of the application. In addition to lubricant chemistry knowledge, the lubrication engineer also must analyze the application based on the identified tribological system. This analysis includes such topics as speed factors, elastohydrodynamic lubrication, extreme pressure lubrication, emergency lubrication and various special application requirements.