【正文】
d at improving methods of quality control for building works, some 501 quality related events were noted. The qualityrelated events were divided into three main areas: design, poor workmanship and other. Design and poor workmanship bined to form more than 90 per cent of the total events listed in Table I. Under poor workmanship lack of care and lack of knowledge were the main causes, whilst in design unclear/missing information and design will not work were identified as the major causes of problems, including the most serious cases. NEDO showed that causes of defects in housing were mainly in design (50 percent) and construction (30 per cent). The remaining 20 per cent were attributed to materials and other causes. WHY QUALITY PERFORMANCE SHOULD BE MEASURED IN CONSTRUCTION Although the above findings reveal failures in building projects, failures among civil engineering projects may be even more serious owing to the greater variety of risk factors. The findings above can be considered as either cause for concern or as inevitable events that are part and parcel of the construction process. It is wellknown that, while the frequency of some failure items is low, they can tremendously affect project time and cost. For a firm to survive, it must strive not only to produce the final product to specification but also to produce it at the lowest cost possible. There is no doubt that most firms, whether in design or construction, are able to produce work to the specification within an acceptable tolerance with respect to time and costs. The magnitude of the tolerance has to be reduced for a firm to remain petitive. Management and production teams must reduce failures that are qualityrelated to the minimum such that there is a reduction in the tolerance gap. In order to do this, the failures must be identified and their seriousness assessed. In construction, many panies have taken up Quality Assurance (QA) as a means of staying in business. Designers, consultants, contractors and even subcontractors are aware of the consequences if they fail to provide a minimum level of assurance to their clients. However, to stay in a highly petitive environment as in the construction industry, not only does quality work have to be offered but also a profit has to be made. Traditional thoughts often have qu