We provide you with the necessary knowledge to carry out the design, execution, and evaluation of validations in chemical testing. We explain the information obtained from Reference Materials, interlaboratory comparison tests, and internal quality controls. We introduce the innovation of performing validations based on a sufficiently large set of interlaboratory test results. The course includes numerous practical examples that will allow you to learn how to estimate the uncertainty of the test method in order to comply with the requirements of the UNE-EN ISO/IEC 17025:2017 standard.