Biomechanical foundations of Aligner Orthodontics. A book that orthodontists can quickly consult whenever a question arises while planning any type of case, knowing they will find up-to-date information on tools, biomechanics, protocols, and optimal sequences—all backed by the latest scientific research. We trust it will fulfill this purpose and become a versatile, effective tool to help our colleagues plan their cases successfully. This book is also available in spanish.