Introduction :Mistakes in the “Total Testing Process” are called “Laboratory Errors.” Laboratory services have a great influence on clinical decision making, hence there is a need to investigate any possible error in the “Total Testing Process.” Errors are broadly divided into preanalytical, analytical & postanalytical categories. A simple practice of maintaining “Error Register” and analyzing the reported errors can pin point at the probable modification required in the process design. Methods :All errors were recorded in a register. The root cause analysis was carried out for each error reported for six months.The necessary corrective action was decided to avoid future errors. In order to know the trend a bar graph was plotted for number of errors per month. Percentage of pre analytical, analytical and post analytical errors was calculated. Results :Among the total errors 75% are pre-analytical, 7.1% are analytical and 17.9% are post-analytical errors. Phlebotomy training for staff & bidirectional interphasing of instruments are most important corrections required. Conclusion :Maintaining an error reporting register is very simple, cost effective and performance improving method.