Singapore is a country built entirely by migrants. The topic of migration thus forms a very important part of the history of Singapore, in which much research has been done. However, one aspect of the modern migration history of Singapore has not been wellstudied, and that is illegal immigration. Since centuries ago, people have been smuggled on the very waterways that modern Singapore owes its prosperity to. Today, people are still entering and exiting the country clandestinely using the same waterways. However, as technology develops, the methods by which these people use to enter Singapore clandestinely are constantly changing. Regardless of the change in methods, such clandestine migration often involves great danger and hardship for those who dare to embark on the journey, just as the way it was in the past. This is even more so as Singapore turns from a colony to an independent country, and as the independent government increasingly exercises more control on the type of immigrants it allows into its borders to help take the country to greater heights in terms of prosperity. Immigration policies and laws thus become fine-tuned and people who are deemed “undesirable” are filtered out. The strict laws did not, however, deter some people from entering the country in search of a good job and a better life. As Singapore gears itself to receive more legal migrants, it must also be prepared to take measures against illegal immigrants. Illegal immigration is therefore a continuous battle between the authorities and the illegal migrants. Through the use of official and unofficial documents and public resources, some of which are not easily obtainable, this thesis traces the development of illegal immigration from a historical context and explores the life of the illegal migrants in Singapore so as to fill in the gaps on an under-studied topic, as well as the change in mindsets migrants-turned-citizens have towards new migrants, in an attempt to use a historical approach to explain the issue of the social phenomenon of illegal migration to Singapore.