Berruto M, et al. – This single–centre prospective study aimed to assess clinical results of Autologous Chondrocyte Implantation (ACI) at an average follow up of 162 ± 27 months (range 88–208) in a group of patients who underwent ACI. For chondral and osteochondral lesions of the knee, ACI represented a valid technique in a population heterogeneous for age, sex and activity level with good results even at a long term follow up.