Although analysts' individual methods may vary without compromising the validity of their conclusions, there are a number of basic, accepted scientific principles for examining bloodstain patterns. The author presents this basic methodology in eight separate steps, which makes it easier to understand each phase of the bloodstain analysis. The first step is data collection, defined as the collection of any information that can assist in determining what may or may not have happened before, during, and after the incident that produced the bloodstain pattern. The second step is case review, which involves learning as much about the case as is currently known. The third step is the isolation and detailed description of bloodstain patterns without any attempt to draw meaning from the patterns. The fourth step is the formulation of hypotheses to be tested regarding the nature of the event that produced each bloodstain pattern. The fifth step is the testing of hypotheses through various scientific processes. The sixth step is the formulation of theories, which are much broader than hypotheses, as they include scenarios of events preceding and following events related to the bloodstain patterns. The seventh step is the testing of various theories, followed by the eighth step, which consists of drawing conclusions from the findings of the analysis. The descriptions of these eight steps should make it clear to a layperson that the testimony is based on a thorough, objective procedure for interpreting bloodstain patterns. 1 figure and 7 references