Accurate mediastinal nodal staging is essential for the management of non-small cell lung cancer (NSCLC), as it refines prognosis, guides multimodal treatment, and improves survival. This joint consensus document from the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) and the Spanish Society of Thoracic Surgeons (SECT) updates and expands the 2011 SEPAR guidelines, incorporating the 9th edition of the TNM classification and extending recommendations to the entire perioperative setting, including both preoperative and intraoperative mediastinal staging. The recommendations were developed through a structured review of the literature and multidisciplinary expert consensus. This document synthesizes current evidence on the role of endoscopic and surgical approaches for perioperative invasive staging, including endobronchial and oesophageal ultrasound-guided techniques, mediastinoscopy and its variants, transcervical lymphadenectomies and intraoperative lymphadenectomies. In addition, the consensus integrates the International Association for the Study of Lung Cancer (IASLC) definitions of completeness of resection and proposes quality standards for intraoperative lymphadenectomy. A practical staging algorithm is provided, stratifying tumours according to risk factors of occult mediastinal disease such as tumour size and radiological nodal involvement. The new recommendations emphasise that invasive mediastinal staging is not required for T1a and T1b tumours without radiological evidence of nodal disease, regardless of their location. Conversely, particular attention is given to the role of N1 disease, which is now recognised as a setting associated with a high risk of unsuspected mediastinal involvement. For cases with intermediate suspicion of mediastinal disease, surgical staging techniques demonstrate superior accuracy compared with endosonography alone. Overall, these recommendations aim to harmonize perioperative invasive staging across disciplines, minimize under- and overstaging, and support precise therapeutic decision-making in the evolving era of targeted and immune-based treatments for NSCLC.