As this overall reconstruction is pursued, specific investigative questions may present themselves-distinct issues that the methodology of Event Analysis alone may not answer. In an effort to resolve them, these significant investigative questions must be considered independently. Once again, the method employed to resolve these questions must be the scientific method. Most discussions on how to resolve such specific questions in a crime scene context simply identify scientific method as the accepted methodology and fail to further explain the process or individual steps required to achieve that end. Functionally applying scientific method is not particularly complex, but it does require an understanding of what the steps consist of and how one goes about applying each step to the question being analyzed. Although it can be argued that scientific method can always be pursued as a mental exercise, when dealing with these critical issues their complexity demands a more formal effort. In this chapter, we will introduce the use of event analysis worksheets as a means of resolving these significant investigative questions. The worksheets utilize a memory aid, “PhD etc,” to help identify each of the six basic steps of scientific method. Lucien Haag first suggested this memory aid and described it as “PhD ic,” which stands for Problem, Hypothesis, Data, Interpretations, and Conclusion.1 We have replaced the “ic” with “etc,” which reminds the user that to employ scientific method, we must also consider Expectations/predictions as well as Testing those predictions and ultimately defining some Conclusion. This mnemonic aid represents a standard procedure for crime scene reconstruction (CSR Figure 4.1).