The concept of a hierarchy of evidence is useful in rapid electronic searching to answer questions arising during the natural course of clinical practice. The answerable question often begins "What is the evidence that ..." and, when focused on a treatment, usually includes a population, an intervention, a comparison group, and an outcome, often called a PECO question. This type of question, concerning the outcome of exposure to an intervention in a defined population relative to the outcome for a comparison group is often called a four-part or PECO question (population/exposure/comparison/outcome). Practitioners posing answerable questions will find the concept of a hierarchy of empirical evidence based on methodological quality especially useful in doing searches with limited time in electronic databases. This article takes a sample scenario and poses the possible steps taken to resolve the problem described in the scenario in the following sections: The Answerable Question; Start at the Top and Work down the Hierarchy of Evidence; Use Software Filters to Speed the Search for Quality Evidence; Combine Methodological Quality with an Assessment of the Risks and Benefits of a Treatment; Combining Quality Evidence with Expert Opinion; and Two Dimensions for Grading Evidence on an Intervention.