原文：Assessment of cost control systemsThe most important function that facilitates construction organizations to accomplish profit maximization is cost control. However, the absence of a well established cost control system has caused failures to many Thai contractors especially during the current economic recession period. To comprehensively understand cost control systems in practice, this study theoretically assessed effectiveness as well as the deficiencies of the traditional systems the effective systems. In addition, by contrasting what are found in effective systems but not found in traditional systems, critical attributes most contributing to the systems successfulness were identified so that the improvement steps can be suitably prioritized. The validated findings indicated remarkable contrasts between traditional and effective systems. Two critical aspects, including advancement of cost control framework and systematic participation of site personnel in cost control, were found to be the major differences. Interestingly, similar conditions were encountered in various countries such as Greece, Pakistan and Australia; hence suggestions from this study could be internationally useful.In actuality, contractors perceive cost control as a pre-requisite factor towards profit maximization. An unprecedented growth in the Thai construction industry since the late 1980s had rotated the market to be the contractors in which high profit margin could be facilely accommodated in bid quotation. A roll of forthcoming projects continually offered and contracted without intermission thus allowed contractors to luxuriate in advanced payment and credit from suppliers. This healthy cash flow situation, unfortunately, could be predominant over real profit materialization. Actual symptoms of unsystematic cost control in most Thai construction companies have been concealed until apparent recession of the economy in 1997. Severe declination of the Thai GDP and construction growth rates shown has given rise to business failures in many organizations. Equally worse, for the others surviving, extremity of nightmares in the ultimately low-demand market is still unpredictable.Cost control system Despite extensive literatures reviewed in cost control, an integrated view of the system was not portrayed. The system functions were mostly discussed in isolated fashion, for instance, estimating budgeting, monitoring and analysing, and reporting. Furthermore, most previous research works concentrated more on theoretical concepts rather than operation in the real-complicated environment.Applying a synergetic approach, the integrated view of the cost control system is proposed to enhance value of past efforts. As a main framework, the cost control system in this paper is defined as a kind of information system that aims to provide management with timely and accurate cost information so that timely proper corrective actions can be taken. In addition, management information can be stored in a historical database and, in turn, serves as a feedback for future estimation. The system consists of three main parts, namely, cost control framework, cost control functions and management information.To solidify a specific set of objectives, a pre-survey of existing cost control systems in Thai large-scale construction organizations was primarily conducted. A contact list of the top 100 organizations in terms of turnover was achieved through collaboration with the Thai Contractors Association (TCA). Each contract ever handled by these organizations covers a project area equivalent to over 30000 or has approximate value of more than 100 million Baht (3 million $US). Introductory letters were sent to the top 100 contractors requesting assistance on the preliminary survey of their cost control systems. Telephone interviews were followed up. Two focal points regarding the recent development of cost control system and the systems ability to indicate the on-going cost status of each work item were investigated.The result elaborated indicated that the cost control systems in most organizations have not been changed much from the past. Out of 100 organizations, only five have initiated a development plan and only two of them have successfully implemented their cost control systems. Based upon this finding, two types of the system can be categorized. First, the traditional system, commonly found in most organizations, is the system that has never been seriously developed and implemented. Secondly, the effective system is the system that has been seriously and continuously improved until management information that facilitates decision making for timely and proper corrective actions as well as estimating process in future projects can be obtained. This type of system, unfortunately, is exceptionally found in a few organizations.ObjectivesTo achieve better understanding of how the existing systems in real practices are