Rapid population growth is a common characteristic of all the GMS countries as depicted in Figure 1. With a population of 180 million in 1990, the region by 2015 was home to 237 million people. Myanmar, Thailand and Viet Nam have relatively higher populations than Cambodia and Lao PDR. They host 91 percent of the total population of the GMS with Viet Nam being the largest with 93 million inhabitants.