Purpose: The paper aims at better understanding the micro-foundations of current institutional changes in agricultural knowledge and innovation systems (AKIS). Design: A survey of 98 farmers and interviews with 37 advice providers in south-western France were conducted to analyse the ways in which farmers combine different sources of advice (microAKIS). The farmers' practices were observed for general farm management and for 3 types of innovation (new crop diversification, digital decision support tools, and labour outsourcing). Findings: The results highlight poorly-known characteristics of microAKIS regarding the variety of sources of advice used by farmers, and the limited number of reliable resources on which farmers can draw at key stages of the innovation process. They provide evidence of bottom-up mechanisms of institutional changes such as the routinization of the use of certain service providers that are often overlooked in AKIS analyses (e.g. upstream industries). Practical implications: These results can contribute to reducing the misalignments of stakeholders' representations of AKIS and microAKIS, and therefore facilitate public debates and improve the efficiency of interventions in this area. Theoretical implications: Studies of institutional changes resulting from the evolution of microAKIS are expected to complement analyses of increased pluralism of advice providers. Originality: Linking the observation of microAKIS and the analysis of incremental institutional changes in AKIS allows the identification of transformations of the AKIS rationale that would otherwise remain partially invisible.