Acquired diseases of the tricuspid valve often occur in combination with and as a result of left-sided heart diseases or long standing atrial fibrillation. The clinical and prognostic significance of acquired diseases of the tricuspid valve was long underestimated and the corresponding diagnostics and therapy was neglected. Instead, the focus was placed on the associated left heart pathology, which was the determinant of symptoms and prognosis. Both tricuspid valve stenosis and regurgitation can remain clinically inapparent for a long time; over time symptoms occur, which can be pathophysiologically traced back to increased venous congestion and reduced cardiac output. The most important and initial diagnostic tool is transthoracic echocardiography in addition to clinical history and examination. In addition to optimal medical therapy for heart failure, which includes diuretic therapy, there are currently surgical (open heart surgery and minimally invasive replacement and reconstruction procedures) and catheter-guided therapy procedures such as the “edge-to-edge repair” using clipping procedures and transcatheter annuloplasty available.