The account of autistic schoolboy Yu Man-hon's shuttle between SAR and mainland immigration counters before he disappeared last August is well documented. Similarly, everyone in Hong Kong has experienced the crowds at border crossings at some time or another, usually amid the chaos of mass migration at holiday times. So it comes as no surprise to learn of the Ombudsman's suggested mechanisms to prevent a repeat of the tragedy. Wisely, the Immigration Department has accepted the recommendations and is making changes. It was evident that the barriers at immigration desks were not adequate to prevent people slipping through unchecked, as 43 managed to do in the three main arrival points last year. And equally obvious that there should be established liaison procedures with police for missing persons. Given passenger volume and family ties between residents in both places, the opposite side of the border is the obvious place to look if someone disappears. When nearly a quarter of a million passengers make the Lowu crossing every day, and more than 10 thousand are undocumented, the importance of state-of-the-art monitoring equipment cannot be overlooked. Recorded video images too small for a clear picture are next to useless. If staff are under pressure, at least the technological back-up should be able to identify anyone who escapes passport checks, so that follow-up action can be taken. It is asking a lot of two supervisors to concentrate on the flow from 31 immigration counters, as happened during the Ombudsman's investigation. If this is the staffing ratio on a relatively normal day, a review of manpower is required. But in Man-hon's case, the greatest concern is the way an obviously mentally handicapped child was passed from one side to the other without anyone recognising him as a special case. The protection the boy needed was not provided. And while Immigration is not a social service, all uniformed government services have a duty to assist the public when they need guidance. That should be a matter of common sense. It should not require special training for one human being to respond to the needs of another who is disabled, especially when a minor is involved. But if a training course will make staff more aware and caring, so be it. The main thing is that a case like this never occurs again.