When research concludes, post-trial access to the trial intervention or standard healthcare can be crucial for participants who are ill such as those in resource-poor countries with inadequate healthcare, British participants testing ‘last-chance drugs’ unavailable on the National Health Service and underinsured US participants. Yet, many researchers are unclear about their obligations regarding the post-trial period, and many research ethics committees do not know what to require of researchers. Consequences include participants who reasonably expect but lack PTA to the trial (...) intervention, unplanned financial liabilities for NHS Trusts forced to fund this, negative press and potential to undermine public trust.1–3,iOne reason for the lack of clarity is controversy over whether and when participants should have access, after the study, to the study intervention. At one extreme is the view that continued access should be ensured when the intervention has benefited the participant or when it has proven safe and effective for the participant population, irrespective of the cost and burden of ensuring continued access. At the other extreme is the view that continued access need never be provided so long as non-availability of the study intervention post-trial was adequately disclosed when participants were invited to participate.6 There is also disagreement about when poststudy access to the study intervention should be considered beneficial for participants. The spectrum ranges from the view that the intervention should be regarded as beneficial for a proposed use only after the …. (shrink)