It has been clear for some time that round-the-clock opening of the border between Hong Kong and Shenzhen is inevitable. The arguments for maintaining the existence of restricted opening times have fallen away gradually until there are now very few voices of dissent. Business has called for the move, the public clearly wants more freedom to choose the time they can cross, and many developers have now come round to the idea that lifting restrictions would not have a negative impact on property prices. The Real Estate Developers Association has even signed a joint submission with other chambers of commerce to lobby for an extension of opening hours. Financial Secretary Antony Leung Kam-chung, who favours proceeding cautiously, has confirmed that 24-hour opening is the long-term goal. It is not surprising then that the reaction to yesterday's announcement that crossing points will soon open for an extra half-an-hour a day has been, on the whole, positive. There are, of course, reservations from some quarters; but these now appear to be in a minority. Pressure on the border is extreme. Every weekday, some 230,000 people travel from Hong Kong to the mainland or vice-versa. Those who argue that certain areas of Hong Kong's economy may feel some ill-effects from extended border opening times are, ultimately, only arguing for protectionism. Integration with the Pearl River Delta is inescapable. Placing obstacles in the way of the free flow of people simply delays this process. Moreover, as mainlanders' disposable income rises so too will the number of wealthy individuals choosing to shop for prestige goods in Hong Kong. The open flow of goods, information and services is what makes the SAR the successful free marketplace it is. The same should apply to the movement of people. Round-the-clock opening of the border should be introduced as soon as possible.