Peripheral T-cell lymphoma (PTCL) constitutes a rare and biologically diverse group of non-Hodgkin lymphomas (NHLs) that arise from clonal proliferation of mature T cells and natural killer cells. PTCLs are aggressive lymphomas with unfavorable prognoses. Outcome varies by subtype, but long-term survival is only about 10-30% for most types. The rarity of the PTCL disorders, together with a lack of randomized trials, means that current treatment regimens are based on those used for B-cell NHLs, typically including combination, anthracycline-based chemotherapy. However, most PTCLs exhibit low rates of response to these regimens, as well as infrequent durable remissions. In recent years, advances in diagnostic methodologies have improved understanding of PTCL pathobiology and have resulted in better characterization of the different subtypes of PTCL. It is now acknowledged that these disorders behave differently than the B-cell NHLs and that each subtype warrants a distinct treatment approach. Development of PTCL-specific treatments has gained momentum, with much research focused on investigating ways to intensify the chemotherapy regimen, such as adding new drugs to frontline chemotherapy and consolidating first remissions with high-dose therapy and autologous stem cell transplant.