Testing more than required will increase project costs unnecessarily [1]. When the project starts, the customer speciˆes what level of quality for the product is expected. ¡e project manager needs to ˆrst make sure that the processes to be followed for building the product are at least so good that the produced product will have a certain level of quality with a certain level of defects. ¡en, he should have a test plan such that the product defects are further reduced by ˆnding defects and ˆxing them. So the testing phase must be well planned with required budget, schedule, and testing processes that will ensure that a certain number of critical defects are caught and ˆxed (Figure 13.1).