One of most important fundamentals in spiritual life, perception and practical creation of people is certainly trust. Without trust, common understanding, creative efforts and constructive social relationships between people would be impossible. In laboratory work, similarly to other businesses, a laboratory result as the initial requisite that could be used with ultimate success in the activity for which purpose it has been issued may be taken as a reliable one. However, in many cases it is very impractical and risky to wait for the outcome of intended activity to see the reliability of laboratory data, so some faster alternative criteria are usually used that include judging of credibility of data in the first place before proceeding with further action. The confidence in final outcome could be enhanced by choosing laboratories or organizations with realized technical standardization and accreditation, with the requested analysis included in the accreditation scope. Recently this system pays due attention to the circumstances that influence the motivation and intent of the data source as well.