Sometimes patient samples may present confusing, complex and conflicting serologic outcomes. In other patients with straight-forward appearing serology, there may be information that would drive the experienced clinician and/or technologist to question the serology results. In both of these cases, the clinical and serologic history, current therapies and additional serologic investigation will help the clinician make the right choices for the treatment and management of the patient. This presentation will include case studies illustrating the problem solving process.