This guide tells you how to use aPriori’s Cost Model Work Bench (CMWB) to customize cost models. It covers how to navigate the resources made available by the CMWB in order to view and modify cost model data, metadata, and logic. It covers the syntax and semantics of Cost Scripting Language (CSL), as well as CSL predefined functions and constants. It also describes how the cost engine, templates, and GCD hierarchy determine the flow of CSL evaluation. Finally, it provides examples of common customization tasks.