The Practical Philosophy of AI-Assistants presents a formal conversation between an AI engineer, Peter, and a humanities researcher, Suman. The book ensures that specialist concepts in AI research are made comprehensible to a humanities researcher, while humanities theories can be easily grasped by an AI engineer. The authors establish ground rules to design an AI-Assistant, that is, an AI system that could act as a personal friend, consultant and confidante for every individual, to be integrated into our daily lives. These rules apply to four large areas of AI development: recognition and identification, communication, explanation, and civility. In discussing these areas, this book provides an accessible account of the current state of AI research, as well as adding nuance to the underpinning assumptions informing the relevant technologies, reflecting on their social implications. The broader ideological objective of The Practical Philosophy of AI-Assistants is captured by the phrase 'practical philosophy', which expresses a commitment to bringing AI development to work towards a good life for all.