Introduction: "Congenital fibrinogen disorders (CFDs), caused by pathogenic variants in 1 of the 3 fibrinogen genes: FGA, FGB, or FGG, are classified as quantitative deficiencies—afibrinogenemia and hypofibrinogenemia—typically inherited in an autosomal recessive manner, or qualitative defects—dysfibrinogenemia and hypodysfibrinogenemia - most often showing an autosomal dominant inheritance pattern. Fibrinogen plays a role not only in blood coagulation but also in wound healing, angiogenesis, and inflammation. Consequently, structural or functional abnormalities of fibrinogen may lead to complex and often variable clinical manifestations. Patients with afibrinogenemia typically present with umbilical cord or mucocutaneous bleeding during the neonatal period, whereas those with hypofibrinogenemia usually experience mild‑to‑moderate bleeding, often triggered by trauma or surgery. In contrast, dysfibrinogenemia may result in either bleeding or thrombosis, and a substantial proportion of patients remain asymptomatic. Although genetic testing has improved the confirmation of CFDs, diagnosis is mainly based on functional and antigenic fibrinogen measurement. Nevertheless, CFDs remain underdiagnosed, mainly due to underestimation of mild or asymptomatic decreases in fibrinogen levels and a limited access to molecular testing in routine practice. Next‑generation sequencing enables a simultaneous analysis of all 3 fibrinogen genes and has substantially increased the detection of novel variants, contributing to a better understanding of genotype–phenotype correlations. Recent reviews have emphasized the marked clinical and laboratory heterogeneity of CFDs and the need for an integrated diagnostic approach combining fibrinogen activity, antigenlevels, and molecular testing. In Poland, to our knowledge, 49 genetically confirmed patients with CFDs have been reported to date. Here, we present clinical and genetic characteristics of 10 unrelated Polish patients with CFDs, with long‑term follow‑up, including 3 novel variants in the FGB and FGG genes." (...)