Clinical diagnosis of a venous thromboembolism (VTE) is often difficult because the symptoms of this disorder are diverse and unspecified. The combination of a low probability clinical decision rule and an unremarkable D-dimer test is a safe way to exclude the presence of a VTE. Clinical decision rules for the diagnosis of a deep-vein thrombosis are available for primary and secondary care and clinical decision rules for the diagnosis of a pulmonary embolism is available for secondary care. Various D-dimer tests are available that differ with regard to sensitivity, specificity and duration of the measurement. During pregnancy and puerperium using a clinical decision rule and a D-dimer test is inadequate: additional radiologic investigation is always indicated in this situation. The diagnostic value of the D-dimer test during suspected recurrence of a VTE is yet to be determined.