The present guidelines for single-laboratory validation of qualitative real-time PCR methods were developed by the international working group "Development of methods for the identification of food produced by genetic engineering", established pursuant to § 64 of the German Food and Feed Code. It aims to ensure that qualitative real-time PCR methods developed by this group are able to meet the performance criteria defined at the European (ENGL, CEN) and international (ISO, Codex) level. The guideline describes the performance characteristics and the minimum performance criteria that should be taken into account when conducting a single-laboratory validation study for qualitative real-time PCR methods. Key aspects are the limit of detection, the specificity and the robustness of the method. The procedure described in this document constitutes a recommendation that has proven itself in practice.