Purpose The impact of bullying and undermining behaviours on the National Health Service on costs, patient safety and retention of staff was well understood even before the Illing report, published in 2013, that reviewed the efficacy of training interventions designed to reduce bullying and harassment in the outputs. The purpose of this paper is to provide an example of a good programme well evaluated. Design/methodology/approach The methodology follows a broad realist approach, by specifying the underlying programme assumptions and intention of the designers. Three months after the event, Q-sort methodology was employed to group participants into one of three contexts - mechanism - output groups. Interviews were then undertaken with members of two of these groups, to evaluate how the programme had influenced each. Findings Q-sort identified a typology of three beneficiaries from the Stopit! workshops, characterised as professionals, colleagues and victims. Each group had acted upon different parts of the programme, depending chiefly upon their current and past experiences of bullying in hospitals. Research limitations/implications The paper demonstrates the effectiveness of using Q-sort method to identify relevant CMOs in a realist evaluation framework. Practical implications The paper considers the effectiveness of the programme to reduce bullying, rather than teach victims to cope, and how it may be strengthened based upon the research findings and Illing recommendations. Social implications Workplace bullying is invariably implicated in scandals concerning poor hospital practice, poor patient outcomes and staff illness. All too frequently, the sector responds by offering training in resilience, which though helpful, places the onus on the victim to cope rather than the employer to reduce or eliminate the practice. This paper documents and evaluates an attempt to change workplace practices to directly address bullying and undermining. Originality/value The paper describes a new programme broadly consistent with Illing report endorsements. Second, it illustrates a novel evaluation method that highlights rigorously the contexts, mechanisms and outcomes at the pilot stage of an intervention identifies contexts and mechanisms via factor analysis using Q-sort methodology.