Prevalence figures on incarcerated adults with retardation range from 3.6 to 30 percent. With individuals who have learning disabilities included, these figures are much higher. The prevalence of incarcerated youths with disabilities ranges from 12 to 70 percent. In the current study, the authors screened 1,716 individuals in local jails in Erie and Niagara, New York, counties. They found that 5.3 percent were mildly retarded and another 5 percent were learning disabled. Of those diagnosed with disabilities, 98.9 percent were school dropouts. More than 66 percent were reading at or below the second grade level. In general, using a conservative prevalence figure of 10 percent and extrapolating it to the national adult prison population, it is estimated that about 120,000 incarcerated individuals nationwide have disabilities and that approximately 45,000 of them are 24 years of age or younger. Using the same 10 percent figure, it is also estimated that 260,000 individuals with disabilities are on probation and parole and that 28,000 youth with disabilities are in juvenile facilities. The Effectively Communicating with Handicapped Offenders (ECHO) project is designed to provide preservice and inservice education for corrections, law enforcement, sheriff departments, youth counselors, probation officers, and others in the criminal justice system. ECHO training materials consist of eight videotapes, each with a supporting manual. The training is intended to help criminal justice personnel recognize the characteristics of individuals with mild retardation or learning disabilities, interact effectively with them, and increase referrals of those with suspected disabilities to correctional and community programs. An evaluation of ECHO indicates that the approach has been well-received in 11 States where training has occurred. 10 references, 2 notes, 1 table, and 1 figure