Recent data indicate that there are large disparities in the use of opioid analgesics to control breakthrough cancer pain (BTcP) in Europe and worldwide. While it is clear that affordability is a key factor, it is certainly not the only one, and other factors, such as cultural differences and overall awareness, are undoubtedly responsible. More work remains to be done to overcome barriers in the use of these medications when warranted. When prescribing a medication for BTcP, it must be considered that its time profile is different from chronic persistent pain. The best control of background pain can best be achieved with a low dose of an extended opioid, and managing BTcP with a rapid-onset opioid, providing a good combination of overall pain control and lower opioid exposure. Notwithstanding their efficacy, greater attention needs to be paid to inappropriate use of opioids. It is important to evaluate patients for potential opioid misuse, including assessment of risk factors, and aberrant drug-taking behaviours must be investigated. In our institution, several measures have been adopted in this patient population in order to prevent aberrant opioid-induced behaviours. The adoption of some or all of these principles, depending on the individual patient and treatment setting, can undoubtedly help to reduce the risk of developing an aberrant behaviour related to opioid use as rescue medication for BTcP.