In functional testing of any software, design of a test suite is the most crucial task for the QA team. As the availability of time for carrying out test execution across releases is always inadequate, it is very important to have a minimal set of test cases that could cover maximum functionality. Generally, people tend to create lot many test cases to cover all possible combinations of parameters and its set of values. These combinations become unmanageably high as number of parameters and the set of value for each parameter increases. It results in too many test cases getting created but actually only fraction of these could get executed because of insufficient time and a large number of defects get leaked to end customer. Most of these test cases are actually redundant as they do not find any defect. So, it is very essential to create an optimum set of test cases without compromising on test coverage. The best method to achieve this is All Pairs Test Optimization. In Harbinger, we have implemented it for many projects, drastically reducing testing efforts and still find most of the defects internally. The method is elaborated in my article, All Pairs Effective Test Design Optimization.