PurposeThis paper examines “how” an organisation, over time, responded, and “what strategies” were mobilised, to conform to a specific audit society-inspired model introduced in Italy by the Decree 231 (D231). D231 requires implementing an internal control and audit model and performance accounting to oversee business activities and prevent misconduct.Design/methodology/approachA case study approach was adopted for in-depth analysis of the response strategies (i.e. avoidance and compromise) and related initiatives, which were mobilised in ITAGAS, a public organisation leader in the methane gas distribution sector in Italy. Participant observation, interviews and document analysis were the primary data sources. Theoretically, our analysis is informed by insights drawn from the institutional complexity perspective (Thornton et al., 2012; Pache and Santos, 2013a, b) and Oliver’s (1991) model concerning strategic responses to institutional pressures.FindingsAdopting D231 generated institutional complexity in our case organisation. The analysis highlights two phases: the voluntary and compulsory adoption of the D231 model. The voluntary adoption occurred via a compromising strategy that involved forms of “selective coupling” (Pache and Santos, 2013a), which allowed the organisation to strategically adopt only those structures/practices that were seen as appropriate and consistent with its organisational logics. The compulsory phase was characterised by broader adoption of the D231 model through symbolic conformity. The case organisation adopted “avoidance” strategies (Oliver, 1991) and “co-habiting means-ends” decoupling initiatives to protect the basic organisational coherence from the regulative prescriptions.Originality/valueThe paper presents original insights into how the D231 model, an example of an audit society-inspired model, unfolded over time in a specific organisation to achieve the desired change towards more responsible and accountable practices. Our analysis suggests the compulsory phase was less effective than when the model was voluntarily adopted. The paper also reveals that, in contrast to the voluntary phase, decoupling strategies were mobilised in the compulsory phase to reach an organisational equilibrium, which facilitated corporate survival; decoupling was the only effective solution to the imbalance generated by the compulsoriness of the D231 model.