<p>In many countries the Smart City programme is one of several initiatives available to municipalities to advance local sustainability. Since not much is known on the factors predicting the interest of individuals holding key positions, the present study tested how representations of Smart cities and variables from the Theory of Planned Behaviour were related to their intention to implement a Smart City programme in their municipality. In this goal, an online questionnaire was sent to all municipalities of French-speaking Switzerland (i.e., more than 600). Two hundreds fourty-one members of the local government or municipal employees filled the questionnaire in. First, various representations of Smart cities are known to exist. For this reason, a latent class analysis highlighted participants’ representations of Smart Cities: social (46.5%), holistic (17.8%), or technological (5.4%). Second and based on the Theory of Planned Behaviour (TPB), we conducted multiple regression analyses to identify factors underlying municipalities’ interest in joining a Smart City programme, included Smart cities’ representations. Familiarity with the concept of Smart City and its perceived relevance (<i>specific attitudes</i>) in the climate-energy-environment areas significantly predicted municipalities’ interest. Additional analyses suggested that the importance attributed to environmental protection by participants (<i>general attitudes</i>) and being in an urban municipality increased familiarity. In addition, holding a social or holistic vision increased perceived relevance. Overall, the present study highlighted that both individual (i.e., participants’) and contextual factors shaped – directly or indirectly – interest in Smart Cities, and that increasing knowledge about this programme is crucial for its promotion.</p>