The selection of a contractor is one of the most important among decisions made by the ownerof a construction. The application of the prequalification procedure enables the selection of themost competent tenderers. Various mathematical models are helpful in carrying out prequalificationprocedure. In the paper, some selected mathematical models are briefly characterized and modelbased on the theory of fuzzy sets is offered. The applied model takes into consideration theowner’s various objectives, as well as different evaluation criteria. The results of the sensitivityanalysis of the model are also presented. Part of a computer software applying an earlier presentedprequalification mathematical model is described.

Materials play an important role in determining the quality and cost of a building, especially in the context of Vietnam’s rapid urbanization today. This study aims to analyze the status quo for supplier selection for construction projects in a developing country, Vietnam. Questionnaires are designed to conduct a survey among several contractors to assess the current situation of how Vietnamese construction enterprises select their material suppliers. Senior managers, project managers, site commanders, site engineers, foreman, office staff of contractors were interviewed. Based on result analysis of 117 valid responses, the most important criteria to consider when selecting material suppliers have been identified, with the most influential ones being price, delivery time, and material quality. However, the supply of materials still reveals some constraints that must be overcome. Vietnamese construction firms should pay more attention to supplier selection to optimize material delivery efficiency. This research contributes to the understanding of the status quo for supplier selection for construction projects in a developing country. This means contractors can adopt suitable measures to select material suppliers for construction projects.

The topic of this paper is the description of the General Contractor Selection procedure using the AHP method. Another aim of this paper – within the scope of decision-making – is the determination of the potential General Contractor’s evaluation criteria and the selection of the best Bidder using the AHP method. We included the description of the conducted tender proceeding for the purpose of the procurement’s subject. As the decision-making options, we adopted four construction companies that submitted their bid. A key element of the studies was the paired comparison of all hierarchical structure elements. We estimated the local weighting coefficients and global priorities of particular decision-making options as well as analysed the vulnerabilities of the obtained results.

One of the contract awarding systems in public sector in Poland is the Design & Build system. In this system, a client concludes a contract agreement with only one company, a contractor, in order to carry out both design and construction of works. While deciding on this form of delivery of a public project, the client is obliged to conduct a single proceeding aiming to select the contractor. In this paper, public works contracts awarded in the D&B system in Poland are analysed, whilst attention was put on the contracting modes and assessment criteria. The results are assessed against the experience of other countries and recommended methods for selection of the Design and Build contractor.

This paper presents a model of scheduling of multi unit construction project based on an NP-hard permutation flow shop problem, in which the considered criterion is the sum of the costs of the works' execution of the project considering the time of the project as a constraint. It is also assumed that each job in the units constituting the project may be realized in up to three different ways with specific time and cost of execution. The optimization task relies on solving the problem with two different decision variables: the order of execution of units (permutation) and a set of ways to carry out the works in units. The task presented in the paper is performed with the use of a created algorithm which searches the space of solutions in which metaheuristic simulated annealing algorithm is used. The paper presents a calculation example showing the applicability of the model in the optimization of sub-contractors' work in the construction project.

For the construction company, tendering is the most popular way of acquiring contracts. The decision to participate in the tender needs to be made carefully, as it affects the condition of the company and is an important aspect in its quest for success. The bid/no bid decision making is a complex process involving a number of factors. The research carried out so far has mainly concerned the identification of the various kinds of influences on contractors’ bidding decisions. The researchers, on the basis of contractors’ opinions, created rank lists in an attempt to categorize the factors. In this paper the author employs factor analysis which belongs to basic methods of multi-dimensional data analysis. The paper’s aim is first to depict an output set of observed variables, that is bid/no bid factors, in terms of a smaller set of latent variables which cannot be directly observed and then to interpret the dependencies between them.

The article presents the tender procedure used to select the best – according to the investor’s requirements – variant of the offer for the General Contractor of a development investment. The subject of the contract was the comprehensive construction of a complex of single-family, semi-detached buildings with a traditional brick structure. In the opinion of the authors of the article, a well-thought-out selection of an appropriate contractor is one of the most important elements of the investment process, because it has a direct impact on the fluency of the construction stage and the future use of the investment, during the warranty period. In addition, a diligently conducted tender procedure allows to minimize the risk of selecting an unprofessional contractor and thus allows to counteract many possible problems and conflicts during the implementation of the subject of the contract. At the stage of the tender procedure, four variants of offers for the comprehensive implementation of the construction of a complex of single-family semi-detached buildings of the following criteria: price (C1), lead time (C2), form of payment (C3), liquidity (C4), experience (C5) and resources (C6). In this article, the authors presented in details the calculation procedure using the ideal point method. Conducting a multi-criteria assessment of variants, based on the selected methods, also clearly verified the strengths and weaknesses of all tenderers, enabling the selection of the best one in the light of the adopted assessment criteria.