Skilled performance improvement professionals will likely cite a specific model that they developed or use to guide them through a Systematic Approach to a particular performance improvement opportunity. Established experts like Harold Stolovitch, Don Tosti, Geary Rummler, Judith Hale, and Margo Murray have their individual views of what constitutes a Systematic Approach to performance improvement. However, all the models are reproducible and have these elements in common: diagnosis, prescription, and evaluation. A representative example is the Performance Consulting Systems Approach model shown in Table 6.2
(ISPI, 2004). The approach shown is not linear, even though it appears so in this model.