A common question that I ask to IMS Systems Programmers and IMS DBA’s is: How well are your IMS production systems running? And the typical answer I receive is: Very well or Excellen. As my discussions go on, I find some common problems that tell me that those systems could run a lot better and more efficiently with a few small changes. This presentation will go into some very common situations that occur in an IMS Transaction Manager environment that could improve your transaction run-time, cut down on CPU and storage usage, and save you a lot of calls from users. Most of the information you need can be obtained from your IMS log datasets and offline reporting. I will go into detail about problem situations (Region Occupancy, WFI/PWFI, Class Assignment) that you may not be aware of, and hopefully give you some ideas that will make you and your management even happier with your Excellent running system.