Artificial intelligence has been utilized to automate and improve various aspects of medical science. For radiotherapy treatment planning, many algorithms have been developed to better support planners. The book provides applications of artificial intelligence (AI) in radiation therapy according to the clinical radiotherapy workflow. An introductory section explains the necessity of AI regarding accuracy and efficiency in clinical settings followed by a basic learning method and introduction of potential applications in radiotherapy. Some chapters also include typical source codes which the reader may use in their original neural network. This book would be an excellent text for more experienced practitioners and researchers and members of medical physics communities, such as AAPM, ASTRO, and ESTRO. Students and graduate students who are focusing on medical physics would also benefit from this text. Key Features: Systematic chapters are designed over the radiotherapy workflow. Describes in detail how AI contributes to a perspective in the future radiotherapy. Typical source codes are included to implement a neural network. The book supports the reader as a developer of AI.