Drawing on the "corporate professionalization" model (Kipping et al., 2006; Muzio et al., 2011) of new strategies adopted by managerial occupations, this paper explores professionalization processes taking into account the role of the client. Based on an analysis of the professionalization of executive coaching, it demonstrates the influence of the client organizations in such processes, at a collective and institutional level. This influence tends to favor new professionalization strategies of differentiation, regulation and dissemination. The paper suggests that this influence does not necessarily limit the power of corporate professionals, at least in the institutionalization phase, especially if we redefine power as consisting "not in restriction and exclusion, but in extension and linking" (Eyal, 2013: 876). Framed primarily to analyze corporate occupations practiced by independent professionals, the “client professionalization” model suggests better taking into account the influence of client organizations in further research on professionalization processes, in line with the research conducted on “client capture” (Dinovitzer, Gunz & Gunz, 2014; Leicht & Fennell, 2001). By studying an emergent corporate profession that is practiced by self-employed, solo practitioners and freelancers, which have been largely overlooked in the literature, this paper contributes overall to a more diverse understanding of corporate professions and the ways in which they professionalize.