A major stream of Artificial Life (ALife) research aims to build synthetic life forms, operating in virtual worlds, implemented as computer programs. A clear long-term target for this research is the evolution of digital life-forms with a complexity of structure and behaviour analogous to biological life-forms, potentially exhibiting intelligence and self-awareness. The creation of intelligent, self-aware digital life-forms has clear ethical implications, but there is no current research into how these ethical issues might be addressed. This paper argues that such ethical research is needed. Furthermore, it describes our future research plans to build a solid philosophical foundation for the consideration of these ethical issues
