One of the most important phases in the construction industry (CI) is the bidding process. During the bidding process, selecting the most appropriate sub-contractors (SCs) for the relevant sub-works is highly critical for the overall project performance. In order to select the most appropriate SCs for the project and prepare the most realistic and accurate bid proposal, general contractors (GCs) have to know all financial, technical and general information about these SCs. Within this context, GCs should consider several factors in the selection process. These factors may include the quality of production, efficiency, employment of qualified members, reputation of the company, accessibility to the company, completion of the work on time etc. This paper proposes a web-based sub-contractor evaluation system called WEBSES by which the SCs can be evaluated based on a combined criterion. It enables GCs to select the most appropriate SCs for their relevant sub-works, speed up the selection process and gain time and cost savings during the bidding process. (C) 2007 Elsevier B.V. All rights reserved.