BACKGROUND: National and international guidance emphasizes the need for hospitals to have effective secondary fracture prevention services, to reduce the risk of future fractures in hip fracture patients. Variation exists in how hospitals organize these services, and there remain significant gaps in care. No research has systematically explored reasons for this to understand how to successfully implement these services. The objective of this study was to use extended Normalization Process Theory to understand how secondary fracture prevention services can be successfully implemented. METHODS: Forty-three semi-structured interviews were conducted with healthcare professionals involved in delivering secondary fracture prevention within 11 hospitals that receive patients with acute hip fracture in one region in England. These included orthogeriatricians, fracture prevention nurses and service managers. Extended Normalization Process Theory was used to inform study design and analysis. RESULTS: Extended Normalization Process Theory specifies four constructs relating to collective action in service implementation: capacity, potential, capability and contribution. The capacity of healthcare professionals to co-operate and co-ordinate their actions was achieved using dedicated fracture prevention co-ordinators to organize important processes of care. However, participants described effective communication with GPs as challenging. Individual potential and commitment to operationalize services was generally high. Shared commitments were promoted through multi-disciplinary team working, facilitated by fracture prevention co-ordinators. Healthcare professionals had capacity to deliver multiple components of services when co-ordinators 'freed up' time. As key agents in its intervention, fracture prevention coordinators were therefore indispensable to effective implementation. Aside from difficulty of co-ordination with primary care, the intervention was highly workable and easily integrated into practice. Nevertheless, implementation was threatened by under-staffed and under-resourced services, lack of capacity to administer scans and poor patient access. To ensure ongoing service delivery, the contributions of healthcare professionals were shaped by planning, in multi-disciplinary team meetings, the use of clinical databases to identify patients and define the composition of clinical work and monitoring to improve clinical practice. CONCLUSIONS: Findings identify and describe elements needed to implement secondary fracture prevention services successfully. The study highlights the value of Normalization Process Theory to achieve comprehensive understanding of healthcare professionals' experiences in enacting a complex intervention.