The article contributes to sustainability transition research by indicating the significance of transformative grassroots innovations in the context of social work research. We introduce the integrative concept of ecosocial innovation in order to demonstrate how grassroots innovations can successfully combine social, ecological and economic aspects of a sustainability transition. By ecosocial innovations, we refer to social innovations with a strong ecological orientation (e.g., recycling workshops, urban gardening, participatory unemployment projects and new local economies). The data consists of 50 examples of ecosocial innovations in Finland, Italy, Germany, Belgium and the UK. We investigate how ecosocial innovations interconnect ecological, economic and social goals and study the factors of their integrative crucial capacity. On the basis of qualitative data analysis and thematic categorisation of ecosocial innovations, we identify five integrative practices: diversity of activities, successful networking, addressing new livelihood, focus on food and explicit conceptual work on sustainability. Very often these integrative practices emerge as pragmatic solutions to local needs. For the participants, the ecosocial innovations can be relevant sources for new livelihood and wellbeing beyond the conventional labour market. Foremost, ecosocial innovations are valuable as forerunners for sustainability transition in practice.