A pre-qualification questionnaire (PQQ) is a document used in the procurement process to assess the suitability of potential suppliers or contractors for a specific construction project. The PQQ is typically issued by the client or the main contractor at the initial stage of the tendering process, or pre-selection process. The primary purpose of the PQQ is to gather information about the interested parties' capabilities, financial stability, experience, and resources. It helps the client or main contractor shortlist candidates who meet the necessary criteria and have the capacity to deliver the project successfully. By prequalifying potential bidders, the client can streamline the tendering process and avoid evaluating proposals from contractors who may not be qualified or suitable for the project. The content of a PQQ can vary depending on the specific project and requirements. However, the PAS 91 is a the standard pre-qualification questionnaire, with standardised questions developed by the British Standards Institute to identify and verify suitable candidates.