A method carried out by a computer verification system for establishing ad-hoc trust between an electronic guide device operated by a guide user and an electronic invitee device operated by an invitee user to exchange sensitive guest data, the method comprising: - the verification system receiving guest profile and guest name-level data as part of a booking procedure, - after receiving guest profile and guest name-level data as part of a booking procedure, receiving a request from a guide device for data pertaining to a specific guest profile, the request comprising guest name-level data presented by the invitee user to the guide user or vice versa, said guide device and verification system communicating through an authorised first communication channel, - transmitting a guest booking confirmation to said guide device, - receiving a connection request from the invitee device through an internet browser accessible public access portal, thereby providing an unverified second communication channel between the verification system and the invitee device, - generating two unique and matching simple keys in response to said connection request, - transmitting a first of said matching keys through said authorised first communication channel to the guide device and transmitting a second of said matching keys through said unverified second communication channel to the invitee device, where said keys are expressible through sense output means (124, 134) of said devices, thereby providing keys on both devices for sensory comparison and verification by said guide user, and - receiving a verification signal from said guide device indicative of a successful key-match performed by the guide user, thereby verifying said second communication channel for exchange of sensitive data by forming a secure communication link between the guide device and the invitee device via the first authorised communication channel and from the verification system and the second, now verified, communication channel. - the verification system receiving guest profile and guest name-level data as part of a booking procedure, - after receiving guest profile and guest name-level data as part of a booking procedure, receiving a request from a guide device for data pertaining to a specific guest profile, the request comprising guest name-level data presented by the invitee user to the guide user or vice versa, said guide device and verification system communicating through an authorised first communication channel, - transmitting a guest booking confirmation to said guide device, - receiving a connection request from the invitee device through an internet browser accessible public access portal, thereby providing an unverified second communication channel between the verification system and the invitee device, - generating two unique and matching simple keys in response to said connection request, - transmitting a first of said matching keys through said authorised first communication channel to the guide device and transmitting a second of said matching keys through said unverified second communication channel to the invitee device, where said keys are expressible through sense output means (124, 134) of said devices, thereby providing keys on both devices for sensory comparison and verification by said guide user, and - receiving a verification signal from said guide device indicative of a successful key-match performed by the guide user, thereby verifying said second communication channel for exchange of sensitive data by forming a secure communication link between the guide device and the invitee device via the first authorised communication channel and from the verification system and the second, now verified, communication channel.