RDI is only available through RDI Program Certified Consultants, although the latter operate in a number of countries including the USA and the UK.
The Connections Center website (the predecessor to the RDIConnect website), accessed on 10 October 2008, states that RDI can only be delivered through RDI Program Certified Consultants who have completed the RDI Program Certification process.
According to Thompson (2009), consultants must undertake re-certification every year.
The certification process is not recognised by any external authorities and the certificate therefore appears to have no external, objective validity.