Sir,External quality assessment scheme (EQAS) is a powerful tool that challenges internal quality control measures adopted by any laboratory. The National AIDS Control Organization (NACO) has implemented the EQAS under Phase III of National AIDS Control Program to bring qualitative improvement in blood banks and human immunodeficiency virus (HIV) testing laboratories. Ours is a full-fledged department of Transfusion Medicine attached to a 500 bedded teaching hospital. We are regularly participating in the EQAS program conducted by NACO. In the present study conducted from October 2010 to October 2013, we evaluated our EQAS results. The coded samples received from the state reference laboratory (SRL) were subjected to two rapid tests with different principles and one enzyme linked immunosorbent assay (ELISA) test. In addition, 20% of all HIV reactive and 5% of all HIV nonreactive samples collected and tested by ELISA in the 1st week of every quarter were sent for cross-checking to the SRL.A total of 24 coded proficiency testing samples were received from SRL for HIV testing during the study period. Of these 13 were reactive for HIV and 11 were nonreactive for HIV. Our test results were 100% concordant with those of the SRL results. Out of 107 samples sent by our department to the SRL in every quarter for cross-checking as per guidelines, 9 were reactive for HIV and 98 were nonreactive for HIV. Discrepant results were obtained on one sample (0.009%). This sample was nonreactive in our laboratory but reactive at the SRL. We recalled the donor and tested a repeat sample, which was again nonreactive by third generation ELISA and rapid method. Root cause analysis of the problem revealed an error at the time of aliquoting the sample.Under the national external quality assessment scheme, the HIV testing laboratories have been categorized into four levels: Apex laboratory, national reference laboratories, SRLs, and district level (integrated counseling and testing center [ICTC] and blood banks). The ICTC and blood banks are monitored by the designated SRLs.[12] All ICTCs participate in an EQAS and have been assigned an SRL. Under EQAS, each ICTC receives coded samples from the reference laboratories twice a year for testing. ICTCs also send 20% of all positive samples and 5% of all negative samples collected in the 1st week of every quarter for cross-checking to the SRL.[3]Samples for proficiency testing or EQAS should be treated exactly as the patient samples. Only then the true situation in the laboratory can be found and fixing the problem becomes easy. It should not be punitive and should only be used for motivating staff to improve quality. We had one discordant result which was due to error at the stage of aliquoting the sample. Discordant results in EQAS program have been reported in a study from North India. The authors attributed discordant results to equipment problems and low sensitivity of kits.[4] EQAS measures the accuracy or bias of results and stability of laboratory testing methods. It also gives the laboratories, both the management and technical staff, added confidence in their test results. It helps to maintain public confidence in a facility and provides scope for continuous improvement.External quality assessment scheme is an early warning system that identifies target areas where immediate intervention is needed including training needs of laboratory personnel. Moreover it benchmarks performance against other laboratories. As a participating laboratory, we have tried to improve our laboratory practices by regular quality control of test kits, procedure and equipment.