The Architecture, Engineering and Construction (AEC) industry has been exposed to working crimes associated with large criminal networks. This paper assesses the connection between criminal behavior and false identities in the AEC-industry in Norway. The study is based on a literature study and nine semi-structured interviews. Actors with different roles related to the work against identity crime were interviewed. False or stolen identities are the key to other criminal activities, leading to the loss of great sums each year, corresponding to 10 % of the global market value in the construction industry. Legit businesses are struggling to compete, and illegitimate businesses are used for money laundering operations. The study shows that the EU expansion in 2004 brought high competition from abroad. Suppliers and contractors that use undeclared work and avoid paying taxes on their services can offer a much lower price than a legit supplier. However, when price is the only selection criteria, it becomes a problem. The jobs where no qualification is required are most exposed. Creating awareness, sharing information and cooperating with the authorities can be a simple yet effective prevention. However, the solutions require constant development.