The subject of this research is related to sustainable tourism and its connection with lifestyle entrepreneurship. The Portuguese business fabric is formed by micro, small, and medium sized enterprises which have emerged in big numbers over the last years, mainly related directly and indirectly to the tourism industry. The discussed issue of this study is whether these companies are a vehicle for sustainable tourism in rural areas. Via a qualitative method, through a comparative case study of 11 businesses, the goal is to evaluate if the lifestyle entrepreneurship initiatives promote sustainable tourism in rural areas, identifying the specific business created and evaluating their growth toward the planned strategies and actions related to internal resources and capacity, as well as marketing. Lastly, the results present the plans made for growth according to the necessary balance among economic progress, environment, public health, and a social context. This study promotes decision tools for entrepreneurs and destination managers as to the practices to be adopted with the goal of sustainable development. Thus, in terms of ecological responsibility, the use of renewable energy through biomass is a very efficient practice because it both produces energy and reduces waste, since the energy production comes from plants and animal waste.