This book presents the issue of access to information in the posting of workers. The authors identify and assess the practices and challenges of construction companies involved in the posting of workers, either as posting companies sending their workers to provide a service from one European Union (EU) country to another or as a user company that receives the services provided by posting companies and their posted workers. The chapters in this book contribute to the debates on the posting of workers by filling a gap in understanding how transnational posting companies and user or receiving companies find and use information in their interaction with national institutions and how that affects their overall performance in terms of the correct application of the posting rules and the protection of labour and social standards. The studies focus on the specific case of the construction sector as one of the main sectors where posting occurs and where both larger companies and SMEs as well as self-employed are active. Consequently, this sector covers a great diversity of “companies”, allowing for a stratified understanding of posting and receiving companies’ challenges.