There is a large variety of factorscontributing or influencing sample quality and components that may be present in samples either introduced (exogenous) or those present in the sample as result of clinical changes (endogenous) "interferents" leading to inaccurate results. Insufficient attention has been placed in promoting the need to improve knowledge by pathology/medical laboratory experts on the range and extent of their influence. As pathology data influences on the average 70% medical decisions with admission, diagnosis and discharge there needs to be greater effort applied from pathology providers to aid clinicians in providing more accurate results and improved patient outcomes, maximizing patient safety. Recognition and identification knowledge or suitable reference source such as this book would be a step in the right direction to reduce patient risks. Sample quality can be influenced by numerous pre-analytical factors starting from patient preparation (e.g. fasting), collection process, choice of collection devises which includes needle size, collection vessel (e.g. anticoagulant choice, anticoagulant effects), sample processing and sample storage.