Delegates travelling to the conference from outside of the UK are strongly advised to check the latest UK Visas and Immigration Department guidance for entry to this country.
At the time of writing, conference delegates may require a Standard Visitor visa. More information, including whether a visa is necessary, is available here.
An important final note: some companies may offer help or guidance to complete paperwork, and charge a fee. This is largely unnecessary (they tend to just complete the very basic forms and return these pre-printed to you) and often inaccurate. Delegates are advised, if in doubt, to use pages on the official UK Government www.gov.uk website.