Name = Ying and Yang pattern I first noticed this problem when I was working as a quality control person in a feed mill. I noticed that when something got out of whack, it showed itself in at least two places. I also noticed that any one anomaly could be caused by any number of things, but a pair was generally caused by a limited number of possible causes. Problem = Identifying the cause of things that have gotten out of balance in a closed system can be difficult to do from outside the system. A closed system being broadly described as a system where the inputs and outputs are well known and measured. Solution = Anomalies within a closed system express themselves in more than one way. Look for pairs of anomalies with well defined and limited sets of possible causes. Consequences = Since pairs of anomalies have smaller sets of possible causes, you can check the possible causes quickly and facilitate a correction quicker. ----- This sounds plausible. But can anybody give an example? It seems to me that it is the examples that are the pattern, not YingAndYang. -RalphJohnson