A great number of potentially worthwhile evaluations are hampered because either the nature of what is being evaluated is not specified or the specification relies upon educational terms that are imprecise or ambiguous. The evaluation must specify whether it is an educational product, or teachers, or perhaps a program that is to be evaluated. If it is a program that is being evaluated, does the evaluation concern the program's goals, the program as described in the program plan, or the program as implemented? Such focal specification is necessary to the context and direction of the evaluation and must be expressed in unambiguous terms that do not permit multiple interpretations. Of necessity, an evaluation will use educational terms to establish focus.