RESUMEN
The term 'external quality assessment (EQA)' has been recommended by WHO consultative meeting in 1980. It has been using to run the retrospective and com-parative statistic tests' reliability among the EQA participants of their organizers. EQA schemes in all fields of laboratory pathology should provide objective information as tools to assist laboratory analysts ensuring the test result quality and on the contrary deciding error-eradicated actions, or more or less improving national test performance quality and standard. Scoring assessment has been designed in the EQA schemes to assist monitoring, and encouraging quality and standard of laboratory performance in the long run of consecutive trials. The Faculty of Medical Technology of Mahidol University now as a collaborating WHO:SEARO EQA organizers, has provided wider EQA schemes, servicing participants all around Thailand, including 400 labs in clinical chemistry of EQAC scheme, 150 labs in clinical hormone of EQAH scheme, 200 labs in clinical microscopy of EQAM scheme, and 190 labs in clinical immunology and serology of EQAI schemes. Regular EQA newsletters, and yearly summer-time seminar and training prove to be the essential education tools promoting both laboratory quality and standard intensively.