A sustainable and environmentally friendly lifestyle provides a never-ending supply of everyday decisions: Do I leave the tap on or off while I shave? Should I buy the expensive energy-saving light bulbs? Should I drive to work or take the bike? Should I become a vegetarian? Although seemingly easy and minor, the mere number of decisions requires us to constantly be on guard; a sustainable lifestyle asks for strong self-control. When we are interested in whether or not a particular individual will act according to sustainable and pro-environmental standards, we need to ask two important questions. First, does this person have strong enough pro-environmental values required to motivate pro-environmental behavior? Second, does this person have the capacity to suppress their egoistic needs and change their behavior to act according to their pro-environmental values?