Value Sensitive Design and Participatory Design are two methodological frameworks that account for ethical issues throughout the process of technology design. Through analysis and case studies, this paper argues that such methods should be applied to persuasive technology—computer systems that are intended to change behaviors and attitudes. Categories and Subject Descriptors K.4.1 [Computers and Society]: Public Policy Issues— ethics; K.4.2 [Computers and Society]: Social Issues General Terms Design, Human Factors Keywords Persuasive technology, design methods, Value Sensitive Design, Participatory Design