This paper examines the role of social and solidarity groups formed under Participatory Guarantee System (PGS) in achieving food security, improving in the income of small farmers and promoting agricultural sustainability (SDG 2). Empirical evidences presented in this paper are exclusively based on the functioning of two such PGS groups (i.e. a non-functional group from Burdwan district and a functional group from Purulia district) in West Bengal. An assessment in compliance with SSE principles (viz. participation, solidarity and innovation, voluntary involvement and autonomy, collective dimension) reveals that these groups embedded SSE principles in their operation, and thereby can be considered as a part of SSE ecosystem. However, an in-depth analysis reveals that the PGS group in Purulia performed better than the other group in Burdwan in three specific dimensions (i.e. participation and solidarity & innovation and collective dimension), which can explain long term sustainability of the group in Purulia. While assessing the socio-economic impact of organic clusters in addressing targeted development goals it is found that formation of clusters do not ensure food availability of farmer households. However, participation in PGS group ensured higher income level of the beneficiaries in Purulia vis-à-vis beneficiaries in Burdwan.