Bias prevention activities undertaken as part of the development process for a major teacher certification testing program in Illinois are described. Because bias concerns were a major issue in planning and implementing the program, three distinct committees were formed to help prevent bias: (1) a bias review committee; (2) a content advisory committee; and (3) a technical review committee. Both statistical and judgmental procedures were used to detect bias, but the small pools of examinees in many fields limited statistical applications. Judgments of educators were the only means of detecting bias in many cases. Additional statistical methods were planned as the program moved into full implementation. An appendix contains the test field codes for the certification testing system. (SLD)