This study sought to understand and improve effectiveness in institutional research (IR) by interviewing, observing, and analyzing resumes of IR practitioners who have been identified by their colleagues as particularly effective in having an impact on decision-making, planning, and policy formation. Ten themes for effectiveness in IR were identified, including understanding your institution, multiple perspectives of its constituents, and academe in general; engagement, visibility, relationships, and trust; helping leaders make meaning of IR findings and use of IR work in the institution; viewing IR as a means to a greater goal; professional colleagues and professional development; workload, time management, and tools; being self-reflective and proactive; attention to detail and quality control; personal and professional qualities; and technical competency. A model of the components of effectiveness in IR is provided. (Contains 2 figures.)