This chapter offers a detailed overview of the essential principles and regulatory requirements involved in the installation, planning, and layout design of radiological imaging facilities. It begins by introducing general planning guidelines, emphasizing the importance of regulatory compliance, adherence to national and international standards, and the incorporation of safety and quality assurance measures from the outset of infrastructure development. Key aspects such as site selection, facility design, and equipment installation are discussed in the context of optimizing clinical workflow, radiation safety, and long-term operational efficiency. The chapter then presents a modality-wise framework for planning, outlining specific regulatory guidelines for imaging modalities including X-ray, mammography, fluoroscopy, computed tomography (CT), and hybrid imaging systems. Comprehensive recommendations are provided for each modality in terms of layout planning, codal requirements, and barrier and shielding strategies. These ensure that radiation exposure is minimized to both patients and healthcare workers, and that facilities meet the structural standards mandated by radiation safety authorities. To aid in practical implementation, the chapter concludes with model layout plans tailored for each imaging modality. These serve as reference blueprints to assist hospital administrators, medical physicists, architects, and planners in designing diagnostic imaging suites that are not only functionally effective but also fully compliant with radiation protection norms.