Title: Project efficiency in the construction industry: A comparative study on the importance of the structure of the contract form for the project managers decision-making process for increased cooperation.  Subject: Bachelor’s thesis in business administration specialization leadership, 15hp Authors: Emma Johansson and Vanessa Dubar Keywords: The structure of the contract form, decision-making process, cooperation, project efficiency Background: The instability and complexity of the construction industry risks leading to effective cooperation falling into the background and the importance of the contract form for implementation results in the industry having to contend with cost overruns, time pressure and unpredictable quality. Research question: What is the significance of the structure of the contract form for the project manager's decision-making process? Purpose: The purpose of the study is to develop an understanding of the structural significance of the contract form regarding the construction project manager's decision-making process to increase cooperation in projects.  The authors of the study strive to compare the project manager's actions in different forms of contracting, where the authors, based on cooperation, wish to see how the decision-making process contributes to the effective implementation of projects.  Method: The study used an abductive research approach and in addition, a qualitative study was conducted where the authors interviewed eight respondents from two different companies in the construction industry. One of the companies carries out projects as a design-build and one company carries out projects as a design-bid-build. The literature study was conducted by collecting existing theory from research studies in the subject area of the study.  Conclusion: The results of the study show that the structure of the contract form is important for the project manager's decision-making process. The contract form has an impact on the structure of the project organization, the management of risks in the decision-making process, communication channels and cooperation, which in turn affects the efficiency of project implementation.