When an evaluator intends to collect quantitative data, an important question that evaluators should raise to themselves is “Will these results estimate population parameters?” If the answer is yes, then the evaluator should check his or her toolbox for the sampling methods that not only address client’s needs, but also most accurately estimate results within identified levels of precision. To accomplish this, the evaluator will need to select a sampling procedure, identify the sampling frame, calculate sample sizes necessary, and determine acceptable error of estimation. Thus, this paper intends to equip evaluators with knowledge needed to understand sampling theory through the most applied procedures of sampling, including systematic, stratified, and cluster sampling.#Instruments #HowTo #Statistics #QuantitativeMethods-TheoryandDesign #GraduateStudentandNewEvaluators #2012Conference #TheoriesofEvaluation