(from the chapter) Assesses the influence of different environmental attitudes and habits on behavioral intentions affecting sustainability. The sample was made up of 253 Spanish citizens. The present work makes an exploratory analysis, selecting a behavioural intention related to a specific efficient behaviour, that is, the intention to adopt or reject a technological innovation for energy-saving: the Night Storage Service for electricity supply. The adoption of the Night Storage Service can be considered an environmentally significant behaviour. Although this service can be supplied without supplementary equipment, its optimum level of efficiency, in terms of economy and energy-saving, is the attainment of efficient behaviours by attitudes and intentions. In this context, ecologically efficient behavioral habits are better predictors than environmental attitudes. The results suggest that a sustainable future for humanity depends mainly on changes in habits and lifestyles.