In microentreprises, considering the management knowledge basis of the entrepreneur, the generation of management innovation (MI) is a crucial question. In this qualitative case study of a microentreprise, we follow Mol and Birkinshaw (2014) who claimed for research on MI generation, highlighting "how relations with external and internal partners can deliver knowledge" (2009). We focus on the entrepreneur-CPA relationship to study how the relationship between the CPA as an external change actor and the entrepreneur as an internal change actor can be a lever of MI generation in microentreprises. More particularly, we aim at understanding how the external CPA knowledge can be internalised by the entrepreneur in microentreprises through the acquisition, assimilation, transformation and exploitation of knowledge. And more particularly, we propose to highlight the key drivers of the generation of MI in microentreprises through the study of the process by which a potential ACAP becomes realised (Cohen and Levinthal, 1990; Lane et al., 2006; Gebauer et al., 2012; Marabelli and Newell, 2014).