The objective of the research is to determine theappropriate factors for contractor qualification byproject owners. The factors used in the qualificationprocedures by either public or private sectors, localor international, were reviewed. This led to aquestionnaire with 73 factors to start with. Interviewswere divided into three groups: project owners (realestate developers), engineering consultants andbuilding contractors. The primary analysis was set toseparate the lower priority factors by using theDecision Index approach. The remaining data wereclassified into two types as objective factors andsubjective factors. The objective factors were selectedand analyzed by Factor Analysis to search for levels ofimportance and relative weights. The subjective factorswere screened by means of questionnaires to the threeopinion groups, taking account of the presentabilityand source accessibility of data. The research proposed two stages in contractorqualification process. The first stage is an initialscreening by using two subjective factors: organizationchart and job description. The second stage is toexamine the specific qualifications by using objectivefactors. In this stage, each opinion group is differentin factor selection as well as weighting. Therefore,the objective factors to be used should be the factorswithin the intersection of at least two groups

14factors met the criterion. In the application of thefactors in qualification models, the relative weightingshould also be considered.