Book excerpt: The Logic Model Guidebook offers clear, step-by-step support for creating logic models and the modeling process in a range of contexts. Lisa Wyatt Knowlton and Cynthia C. Phillips describe the structures, processes, and language of logic models as a robust tool to improve the design, development, and implementation of program and organization change efforts. The text is enhanced by numerous visual learning guides (sample models, checklists, exercises, worksheets) and many new case examples. The authors provide students, practitioners, and beginning researchers with practical support to develop and improve models that reflect knowledge, practice, and beliefs. The Guidebook offers a range of new applied examples. The text includes logic models for evaluation, discusses archetypes, and explores display and meaning. In an important contribution to programs and organizations, it emphasizes quality by raising issues like plausibility, feasibility, and strategic choices in model creation.