There is a growing consensus that cellular immune responses are associated with the clinical outcome of hepatitis C virus infection (HCV). The development of Tetramer staining, ELISpot, flow cytometry and epitope mapping technologies make it possible to enumerate, phenotype and assess the proliferation and function of HCV specific T cells; as well as map and predict T cell epitopes and track the evolution of T cell epitopes. Such information is essential for the development of effective therapeutic and prophylactic HCV vaccines. This article summarizes the technical advances relevant to HCV specific T cell responses.