Unsustainable food production and consumption patterns are threatening our living environment and our lives on earth. There is a need for profound transition in our ways to produce and consume food. Food, its production and consumption is a hot topic currently – as can be seen in media and in several projects run by various institutions. Circular economy and sustainable resource management address different actors as well. The City of Lahti joined the FISU-network and is taking steps towards sustainable resource management. This thesis contributes to the ongoing work of the City of Lahti in developing its food sustainability strategic work through its participation in the FISU-network. The study aims to investigate the state of the regional food supply chain of Lahti, Finland, and its path on sustainability transition. Further on, it examines how alternative food networks may impact different aspects of sustainable local development and what kind of a role actors of regional food supply chain play in promoting food sustainability. This study applied a case study approach and used qualitative research methods in the forms of workshop and semi-structured interviews. The results were examined applying the theoretical framework which included Activity theory, Co-Creation and Economy of Common Good. There are various policies and strategies on global, national and regional level aiming to sustain the food system, food production and consumption, as well as promoting the use of local food. Few of them were used to reveal the present state of the regional food supply chain together with the results gained at the workshop and interviews to find the desired way. Alternative food networks may shorten the food supply chain and allow everyone a chance to contribute to local food sustainability. They may have social meaning by bringing the food supply chain actors together and offering more value than purchasing goods. Consumers can act as co-creators having possibility to influence what is produced, where and how. Alternative food networks may not necessarily be ecological, but they may have wider implications for the regional and local communities on economic, social and cultural levels by offering jobs, interaction, as well as giving a face and a story to the food.