The interrelated socio-ecological crisis our time is facing is leading to increasing pressure on the planet resulting in climate change, combined with increased inequalities. This poses the question of how much energy we consume as a society, and towards what aim, and by whom it is consumed. There is a call for a drastic change in our consumption patterns towards reducing the quantity of resource we use, including energy. This goes together with the need to account for discussions around the possibility for everyone to live a good life. The notion of sufficiency – defined as combining reduced consumption together with fundamental human needs satisfaction – is emerging as an interesting way to address these issues. The research on which this PhD thesis is based engages with social practice theory to describe everyday consumption in the present and the future, in relation to fundamental human needs satisfaction as way for accounting for wellbeing, a normative outcome of how practices are organized. It addresses sufficiency in relating social practices to human needs, through the concept of satisfiers and practices-as-satisfiers – or the practices that allow to satisfy needs. To better understand how consumption reduction can be discussed in relation to needs satisfaction, this work proposes to discuss how change can come about in relation to planned sufficiency, unplanned sufficiency, and planning sufficiency. In relation to these notions, the thesis proposes four empirical chapters, describing: 1) a study of planned sufficiency, through the example of people who decided to ‘live degrowth’, towards a more collective and needs-oriented interpretation of sufficiency; 2) a study of unplanned sufficiency, through the example of ‘lockdown practices’ in Europe during the Covid-19 pandemic, as a window of opportunity for informing sufficiency possibilities; and 3) a study on planning sufficiency, through the transdisciplinary design of alternative imaginaries in the form of energy scenarios and 4) participatory workshops, where living well with less in the future was discussed. The PhD dissertation offers a new conceptualization of sufficiency, defined as the collective efforts that would ensure the necessary conditions for all people to perform practices-as-satisfiers at low levels of material and energy consumption, towards synergic needs satisfaction. It builds on such a conceptualization for taking a step further and making the work relevant at the policy level, by proposing an exploratory process for implementing sufficiency at the collective level.