## 1 Introduction  
Most organizations are interested in digitalization through the implementation of Industry 4.0, enabling technologies to automate processes and pave the way for digital transformation activities to create new business values [1], positively impacting organization growth, structure of value chains, and nature of work itself [2]. Digitalization also creates new opportunities, improves employment and skills [3], and supports new business models [4]. Additionally, Industry 4.0 and the implementation of its enabling technologies can support the optimization of time and costs, enable adaptation to change and new business models [5], and help organizations gain a competitive advantage through the improvement of innovative and competitive products [6]. [PERSON] et al. [7] and [PERSON] et al. [8] studied the role of Industry 4.0 enabling technologies and digital solutions in project management success. The implementation of Industry 4.0 enabling technologies has prerequisites that can be integrated into the organization to enhance digital readiness, facilitate transformation toward Industry 4.0, and minimize failure risk [9]. The prerequisites for the adoption of digital solutions and the implementation of Industry 4.0 technologies are described in this research with their broad perspective and collective role in project management success under the term \"Digital Infrastructure\". One of the generic prerequisites linked to the business strategy in organizations is the continuous improvement process [10]. Having an established business strategy will facilitate the successful implementation of Industry 4.0 enabling technologies and hence empower the decision-making process for project management success. Common prerequisites identified irrespective of the implemented technology are large internet capacity, cyber security systems, Machine to Machine communication, competent employees, access to real-time data, and financial resources [10; 11]. [PERSON] et al. [12] highlighted the organizational culture encouraging and supporting technological innovation as a prerequisite for the adoption of Industry 4.0. Furthermore, [PERSON] et al. [7] identified four focus areas needed for practitioners in a project organization to establish a digital infrastructure that enables project management digitalization. These focus areas are technology, culture, business models, and theoretical lenses. In this paper, the prerequisites pertaining to Industry 4.0 enabling technologies and their implementation in the organization will represent the first pillar of digital infrastructure and will be referred to as \"digital tools\". The prerequisites pertaining to the presence and implementation of general technologies in the organization, the adoption of business models, and theoretical lenses will represent the second pillar and will be referred to as \"digital readiness\". Finally, the prerequisites pertaining to the organizational culture in relation to employees and teams, enabling them to play their roles in properly implementing digital tools in a digitally-ready organization in pursuit of project management success, will represent the third pillar and will be referred to as \"digital fitness\". Accordingly, digital infrastructure refers in this article to the set of digital tools, combined with digital fitness and readiness required to achieve the project management goals and enable the project management practice towards project management success. Digital infrastructure was defined based on the three aforementioned pillars that represent the three main requirements for an organization to be entirely equipped with the necessary infrastructure for digitalization and Industry 4.0 transformation. The existing literature has acknowledged the importance of digital infrastructure in project management, but the relationship between digital infrastructure and project management success has only been explored in the context of Industry 4.0 enabling technologies and their implementation. For example, the work of [PERSON] et al.