Findings were based on information from inmate samples in 11 prisons in California, Michigan, and Texas. The samples, totaling about 1,300 inmates, were selected by a process which ensures that they are representative of incoming inmates in their respective States. Inmate information was derived from official corrections records and the Inmate Survey -- a detailed questionnaire completed by each inmate. For inmates 25 years of age or older, having a prior prison commitment sufficed for designation as a career criminal. For younger inmates, a career criminal was one who had served a prior prison term, or had three or more serious felony convictions or one serious felony conviction plus a serious juvenile record. By this definition, career criminals comprised the following segments of the inmate samples: California, 49 percent; Michigan, 43 percent; and Texas, 42 percent. Areas examined were the career criminals treatment needs, participation in relevant programs compared to other inmates, and unique prison behavioral problems evidenced by career criminals. There was no significant evidence that the career criminals have greater treatment needs than the general prison population or that they participate less frequently in relevant prison programs. Also, career criminal inmates were not found to be the greatest source of prison violence. Younger inmates committed more serious and frequent infractions of every type. There is no indication, therefore, that a prior criminal record that qualifies an inmate to be labeled a 'career criminal' provides documented grounds for treating such an inmate differently in prison. Thus, correctional treatment should be based upon actual behavior while in prison, without reference to criminal history. Endnotes are provided.