Computer-based curve-fitting procedures are now almost universally available. They offer several advantages over manual procedures. Apart from greater speed of execution, they are objective - rather than subjective - so that a given, fixed, procedure will always yield the same values from the same set of data. This paper examines and explains the several stages that are involved in establishing and applying an appropriate procedure. These stages have been incorporated into an Excel program that is available as an example of the principles involved. The several stages that are involved in acceptable computer-based saturation curve analysis can be expressed as: Curve Selection, Curve Fitting and Parameter Analysis. A table containing ten sets of Almen arc height versus peening time data is included (Table 1). These data sets, representing a wide range of practical peening conditions, are being promoted by the SAE as a 'test for acceptability' for saturation curve-fitting programs. Each 'target value' in Table 1 represents the average of calculations made by several different organisations.
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