This peer-reviewed paper seeks to set up a unified system of floor numbering in cosmopolitan cities like Hong Kong where the local culture fosters a liberal practice of skipping certain unlucky numbers in floor numbering. The paper examines three popular approaches in floor numbering: the first approach permits no omission of more than two floor numbers in a consecutive series and any omitted number has to be substituted with the floor number of the floor immediately below it with a suffix; the second approach allows the omission of floor numbers 4, 13 and those ending with 4 without replacement; the third approach suggests that floor numbers should be assigned in strict accordance with their plain meanings. The analysis suggests the following rules to be included in a new piece of legislation. First, the ground floor should, in general, be the floor at street level. Secondly, as a general rule, for floors above the ground floor, floor numbers are to be assigned in a logical and consecutive numerical series; the floor immediately above the ground floor should, without exception, be numbered as the 1st floor. Thirdly, the discretion of omitting floor numbers can be exercised only under the first approach, which in the opinion of the author best entertains the need for clarity as well as the necessity for a certain degree of flexibility. The finding of the research will be instructive to the Government as well as developers, contractors, management corporations and conveyancing lawyers in Hong Kong. It also provides valuable guidelines for law-makers in countries teemed with high-rising buildings. Along with the discussion on floor numbering, this paper sheds light on how law-making should take into consideration of unique social phenomenon in a particular jurisdiction. It has great significance in the culture and practice of land development in Hong Kong and other metropolitan jurisdictions.