For most patients with low back pain (LBP), imaging tests such as x-ray, MRI, and CT scans have limited use in diagnosis and treatment, and are not recommended by research. However, these tests are still commonly used in clinical practice. While several interventions have been developed to reduce imaging, the effectiveness has been variable. This could be due simply to ineffectiveness of the intervention, or it could be due to poor implementation of the intervention during the study period. For example, if the intervention was delivered inappropriately or not at all, it may not be that the intervention was ineffective, but instead, we are unsure if the intervention was ineffective because it was not used properly. The latter case describes the concept of intervention fidelity, which is how well intervention components were delivered; this was not assessed in many of the previous studies. Assessing intervention fidelity during a study can help us better interpret the study's findings on intervention effectiveness. However, assessing intervention fidelity before a main study starts, for example, in a pilot study or by asking a sample of the target population to identify barriers to using the proposed intervention, can help us understand how to optimise the intervention to be more feasible and pragmatic, thereby reducing research waste. The proposed research will use interviews to explore strategies to ensure intervention fidelity of a multi-component intervention designed to reduce imaging for LBP by general practitioners and chiropractors in Newfoundland and Labrador. The findings will play a role in improving interventions aimed at reducing imaging for LBP in several Canadian provinces, improving care for patients and the sustainability of the healthcare system.