This chapter focuses on the voice and experience of energy engineer Joy Clancy, a leading advocate in the area of energy and gender, particularly through her role as a founder-member of ENERGIA: the International Network on Gender and Sustainable Energy. It discusses Joy's experience and reflections about energy studies, the dominance of engineering, technical fields, the place of 'gender expertise' amidst. The chapter considers the Joy's approach towards persuading the unconvinced coupled with her desire to build an evidence base for policy, and the pragmatics of 'efficiency' and 'numbers' as credible frames and forms of knowledge within gender and energy work. In other words, it may be a dangerous assumption that women's economic empowerment will lead to gender equality. The context for Joy Clancy’s work on gender and energy began during a period marked by crises in energy supply: the geopolitical dynamics of access to oil reserves for countries of the global North, and fuelwood shortages in the global South.