Good evidence is not necessarily a high priority for intervention. In fact, a high priority for intervention may lack good evidence. An evidence of priority is not a priority of evidence. It is additional evidence. Evidence surrounding a single question and covering the same problem must be brought together in a logical way, as seen in Chapters 11 and 12. Also, evidence supporting different questions in the chain of medical reasoning must be organized as organically as possible in the process of medical decision-making. This chapter will discuss how to build, interpret and evaluate the chain of evidence supporting each link in choosing the best options for diagnosis and treatment.