Deleterious germline variants are now recognized as common drivers of hematopoietic malignancies (HMs) and bone marrow failure syndromes. With the increasing use of personalized medicine and the application of tumor-based profiling via next-generation sequencing, diagnosis of HM predisposition occurs with increasing frequency. Although deleterious germline variants can be readily identified by comprehensive clinical testing, numerous barriers exist for many clinicians. Observations regarding particular germline predisposition disorders challenge widely held assumptions about these conditions. Here, we review approaches to germline genetic testing, highlighting key points in a typical patient's course that present challenges for testing and interpreting results. Increasing awareness by health care providers of these conditions and improvements in testing platforms are crucial for enabling a proactive approach to tailoring a suitable treatment plan and surveillance program for the patient and their family members.