A scale for measuring self-assessment of factors, which might lead to unintended biases and prejudices, was tested with 39 professionals working with adolescents on probation. The scale has 10 items (e.g., "Would feel comfortable providing clinical services to [e.g., African Americans]." Each item was rated on a 3-point scale so as summated scores increase across items the probability of unintended biases and prejudices against five culturally diverse groups (African American, American Indian, Asian, Hispanic, and White) would also increase. The coefficient alpha was .87. Participants' mean unintended bias and prejudices across items were always lower toward clients from their own racial or ethnic group. For example, Hispanic and White participants tended to be more prompt to display these attitudes against African Americans, relative to African-American participants. White participants, however, reported lower scores leading to unintended biases in the case of White clients, relative to African-American and Hispanic participants. Overall, participants' mean unintended bias and prejudices against American Indian and Asian clients tended to be higher with these groups, relative to clients from the African-American, Hispanic, and White communities. Results are discussed in terms of further development of the scale in the design of cross-cultural training in various working environments with culturally diverse clients.