The European Society for external quality assessment (ESfEQA) offers a variety of external quality tests to medical laboratories in the areas of biochemistry, hematology, immunology and microbiology.Monthly and quarterly programs from ESfEQA are available to the users and managers responsible for quality standards in medical laboratories. The ESfEQA quality assessment samples and the ESfEQA service are characterised by a high quality, reliability, simplicity of use and flexibility.