The trans-septal approach for mitral valve surgery was described byDubost and subsequently modified by different authors. The developmentof this technique was based on the advantages that would have on theusual approach through a left atriotomy below the interatrial sulcus. Theaccess through trans-septal approach allows a greater exposure of themitral leaflets and subvalvular apparatus, especially in small atria, in reoperationsor when it is combined with the tricuspid valve disease. Theaim of the study was to evaluate advantages, technical difficulties,drawbacks and complications associated with the trans-septal approach. Thirty patients with mitral valve disease randomized into one groupunderwent mitral valve surgery through a trans-septal approach. Themean age was 51.16 ± 11.42 years with a range from 23-61 years,(83.33%) of them in NYHA class III and (76.7%) had atrial fibrillation.Standard aortic and bicaval cannulation with antegrade bloodcardioplegia was adopted and tricuspid repair was done on clampedarrested heart. In our study group, the trans-septal approach was performed withno technical difficulties and an appropriate exposure of the mitral valveand its subvalvular apparatus. Complication was observed in threepatients with no mortality. On the other hand no pemenant impairment of atrio-ventricular conduction, no persistent nodal rhythm and no residualdefects in the interatrial septum during the early postoperative periodswas verified. The trans-septal approach has proved to be an excellent altemativethat provides wide exposure of the mitral apparatus for any kind of mitralprocedure, This approach was specially recommended for patients withsmall left atrium, in elderly patients with friable tissues, in re-operationswith previous aortic-valve implantation , when a concomitant tricuspidsurgery is required, with dense pericardial and organized left atrialthrombus. In this series, we observed no conduction abnormalitiessecondary to the procedure and no instances of residual interatrialcommunications. We propose this approach as a very safe one that yieldsexcellent exposure and no morbidity.