• Changing policy. PPI is a fast-evolving area of public policy. While there is a clear obligation for PCTs to involve patients in decision-making, there is no single approach that is recognised as best practice. While this can stimulate valuable innovation, it can also lead to confusion, which is counter-productive.
• Resources. It can be difficult to conduct effective PPI work in small commissioning teams with tight deadlines to meet. With many PCTs working to avoid deficits, the costs of carrying out PPI work can be difficult to meet.
• Gaps in knowledge and skills. Not all commissioners have access to the specialist knowledge needed to ensure that PPI is effectively carried out. Effective focus group moderation, for example,  requires training as well as time.
• Lack of evidence. PPI programmes are not all costed and evaluated as they should be. This means that even successful initiatives are not always credited with the benefits they have brought.
• Representativeness and accessibility. Certain groups within the local community can be easier to reach than others, with the consequence that some people miss out on the chance to have their say. This problem can be worsened if meetings and other events are not easily accessible. Allowances must also be made for the fact that many of the people who want to get involved are service users, and may not always be able to make a substantial time commitment. Equity lens reviews could be utilised to help ensure that no group is disadvantaged by the implementation of the service, but  they must be carried out with care.
• Exclusive terminology. Patients and health professionals do not always conceive of things in the same way. For managers and clinicians, particular issues may be divided into silos, while for patients, the debate is a broad one. For people who are unfamiliar with the structures of health policy or their local PCT, this can be a huge barrier to involvement. However, it may be that the proposed Local Involvement Networks (LINks) can help to overcome this problem - particularly by integrating involvement in health and social care.

This list of barriers was generated at a roundtable discussion in December 2006 which included representatives of Asthma UK, the British Heart Foundation, the Commission for Patient and Public Involvement in Health, the Department of Health, Diabetes UK and the Picker Institute, along with some of the expert commissioners behind the guidance on this site.