The Individuals with Disabilities Education Act (IDEA) greatly improved the educational opportunities for students with disabilities. Teachers require knowledge of the law to deliver necessary and appropriate services to students with disabilities. The purpose of this quantitative study was to examine teachers' knowledge of special education policies and procedures as outlined in IDEA, possible factors associated with teachers' accurate knowledge, and whether or not teachers accurately perceive their knowledge. A sample of 111 Missouri public school teachers completed an online survey. Overall, the findings revealed that teachers lack knowledge of special education policies and procedures; however, special education teachers demonstrated more accurate knowledge than general education teachers. The most significant predictors of accurate knowledge were completing more special education courses and having positive attitudes toward inclusion. Discussion of these findings and implications for training are provided in terms of improving teachers' knowledge and implementation of IDEA.