Mantle cell lymphoma (MCL) is a well-defined lymphoid malignant disease characterized by a proliferation of mature B lymphocytes expressing CD5. This rare lymphoma regroups in fact a spectrum of morphological, phenotypic, and clinical pathologies with at least three diseases: the classical nodal MCL, the most common entity, the indolent leukemic/splenic MCL, and the blastoid variant associated with a very aggressive behavior with poor response to treatment. The genetic hallmark is the t(11;14) (q13;32) leading to the overexpression of cyclin D1 (CCND1). Over the last decade, there has been a large consensus to treat younger patients in first line with cytarabine-based therapy with the incorporation of rituximab and high therapy followed by autologous stem cell transplant. In older patients, the main improvement has been realized by the addition of rituximab as maintenance therapy. However, there are a number of new highly active targeted therapies that are moving into the clinic that are set to transform the therapeutic paradigm for the disease in the near future.