Blood tests are frequently recommended and performed in investigating disease in exotics. However, little is understood about the numbers we get back from the lab – often ‘normals’ are improperly derived or based on low numbers in studies. The tests carried out are those available and may not be applicable in the species being tested. As such there are considerable areas of doubt in many interpretations. This can be especially frustrating in complex cases where bloods may be taken to establish diagnosis when clinical signs are nebulous and generalised. Blood testing should always be regarded as a piece of the investigation and not a fall back to short cut or replace other investigations – we should always treat the patient and not the results! This talk concentrates on tortoises and rabbits and will discuss individual organ assessments and the role of haematology in these species. It will highlight areas of doubt where clinicians should be wary of over-interpretation. It will also discuss clinician/handling artefacts and how these may also mislead as well as the advantages and disadvantages of external vs in-house laboratories.