The EU-funded project HANDS was aimed at assisting young people with an autism spectrum disorder to increase their participation in social life. The core of the project was the development of a mobile device using personalizable software utilizing persuasive technology techniques. This chapter analyzes the ethical issues raised by the project itself and some of the broader issues raised by the use of persuasive technologies in a population with autism spectrum disorder. These include issues relating to consent and assent procedures, the potential conflict of interest of teachers as researchers and co-producers of knowledge, and questions concerning privacy and parental access to data. In addition the chapter also provides an account of the advice given by the project's ethics advisory board.