Patients with advanced non-small-cell lung cancer (NSCLC) carrying epidermal growth factor receptor (EGFR) mutations can now have specific treatment based on the result of biomarker analysis and patients with rearrangements of the anaplastic lymphoma kinase (ALK) gene will probably soon be able to. This will give them better quality of life and progression-free survival than conventional chemotherapy. This consensus statement was conceived as a joint initiative of the Spanish Society of Medical Oncology (SEOM) and the Spanish Society of Pathology (SEAP), and makes diagnostic and treatment recommendations for advanced NSCLC patients based on the scientific evidence on biomarker use. It therefore provides an opportunity to improve healthcare efficiency and resource use, which will undoubtedly benefit these patients. Although this field is in continuous evolution, at present, with the available data, this panel of experts recommends that all patients with advanced NSCLC of non-squamous cell subtype, or non-smokers regardless of the histological subtype, should be tested for EGFR gene mutations within a maximum of 7 days from the pathological diagnosis. Involved laboratories must participate in external quality control programmes. In contrast, ALK gene rearrangements should only be tested in the context of a clinical trial, although the promising data obtained will certainly justify in the near future its routine testing in patients with no EGFR mutations. Lastly, routine testing for other molecular abnormalities is not considered necessary in the current clinical practice.