Continuing professional development (CPD) is expected to maintain pharmacists’ competence, yet participation does not consistently become sustained practice change. To explain what CPD arrangements change pharmacy practice, for whom, through which mechanisms, and under what workplace conditions. A realist review used six PubMed-indexed search routes plus supplementary citation searching on 13 September 2026. Of 76 surfaced records, 15 duplicates were removed; 61 records were screened, 44 reports were sought, 40 were assessed in full, and 24 evidence units were included. Evidence was appraised for relevance, richness, and rigour and synthesised as context–mechanism–outcome (CMO) configurations. Four interacting CMO families explained variation: motivation; workplace opportunity; feedback and social reinforcement; and time, resources, and managerial support. Capability and confidence could rise without enactment when opportunity was restricted, while participation could coexist with weaker autonomous motivation. Repeated practice depended on actionable feedback, legitimate opportunities to act, and organisational capacity. CPD is most plausibly linked to sustained practice change when learning is meaningful, enactable in routine work, reinforced socially, and supported over time. Attendance, knowledge gain, or confidence alone should not be treated as sustained behaviour change.
