Sequential analysis is concerned with statistical evaluation in situations for which the number, pattern or composition of the data is not determined at the start of the investigation but instead depends upon the information acquired throughout the course of the investigation. The formal start of sequential analysis originates in ballistics testing for the Department of Defense (DOD), but we find that the use of sequential analysis is underutilized in the DOD. Expanding the use of sequential analysis has the potential to save costs and reduce test time. In this paper, we provide a brief introduction to sequential analysis, describe its current and potential uses in operational test and evaluation (OT&E), and present a method for applying a sequential analysis to the test and evaluation of defense systems. We perform simulation studies and apply the method to a case study to evaluate the proposed method. Additionally, we discuss challenges that will need to be addressed for sequential analysis that are relevant for OT&E.