Physical growth in weight, length and head circumference during infancy and early childhood (the first two years) of Hong Kong children born in the 1960's and 1970's have been compared with a widely used international reference standard (National Center for Health Statistics). During the first 3-6 months the mean growth curves closely follow the reference mean. Over the following 6-12 months however, there is a distinct downward deviation. From about 18 months onwards the growth trajectories once again closely parallel the reference. This 'faltering' of physical growth, which shows some similarities with that described by young children in poor parts of the world has been attributed by some to less than adequate nutrition during the weaning period. Yet over the past 20 years or so Hong Kong has very much become part of the developed world. This apparent paradox leads us to speculate that genetic influences might play an important role in the faltering of growth.