Educational research is becoming increasingly sophisticated and as a result analyses used to answer research and program evaluation questions are becoming increasingly complex. In the past few years hierarchical linear modeling (HLM) has been used more frequently, not because it is "the next fad," but because it is well-suited to deal with what is known as the "nesting problem" — students share the same teachers, teachers work within the same school, and schools operate within the same district --- a situation that creates interesting statistical issues. The purpose of this presentation is to provide a rationale for the use of HLM, a summary of HLM models, some guidelines for when it should be used, and an overview of how to conduct HLM analyses. The intended audience is practitioners, students, and faculty members who are not familiar with HLM, but would like to be. Sponsored by the Convention Committee and the Society for the Study of School Psychology.