have not shown sufficient response to Tier 1 and Tier 2 interventions. This type of targeted instruction is delivered for a minimum of two 30-minute sessions every week for nine to twelve weeks. The interventions in this tier may be similar to those in Tier 2 except that they are intensified in focus, frequency, and duration. The instruction in Tier 3 is typically delivered outside of the general education classroom. Programs, strategies, and procedures are designed and employed to supplement, enhance, and support Tier 1 and Tier 2 instruction by remediation of the relevant area and development of compensatory strategies. If Tier 3 is not successful, a child is considered for the first time as potentially having a learning disability. In some cases, Tier 3 is considered to be special education, with instruction being provided to individual students or small groups by special education teachers in place of general education instruction (rather than as a supplement). Initial goals are established through an individualized education program (IEP), which is guided by the results of a comprehensive evaluation, and ongoing progress monitoring helps to direct the teaching process. Special education instruction likely will be considerably longer than the 10 to 12 weeks of supplemental instruction delivered in Tier 2 and beyond. The frequency of special education instruction depends upon student need, and the criteria to exit special education are specified and monitored so that placement can be flexible. RTI implementation The number of schools implementing RTI continues to grow and 61% of schools surveyed in 2010 indicated that they had fully implemented or were in the process of implementing RTI. However, most schools in the survey indicated that the continued to focus on reading interventions at the elementary school. RTI is primarily implemented by grade-level teams or professional learning communities as part of a school-wide problem-solving plan, and previous research found that implementing RTI resulted in several positive outcomes such as reductions in students referred to and placed into special education, more students passing state accountability tests, and increased academic skills among students at-risk for reading failure. Fidelity of implementation In an RTI model, fidelity is important at both the school level (e.g., implementation of the process) and the teacher level (e.g., implementation of instruction). Although the concept of fidelity of implementation is supported by research and is generally viewed as common sense, there are practical challenges associated with achieving high levels