Opium smokers in Singapore relax in a sparsely furnished opium den in 1941, suggesting that the clientele were mostly working class. It was a place where you do opium and hang out, then do more opium.

An opium den was an establishment where opium was sold and smoked. The social impact was huge and damaging, with addicts prone to sell all their possessions to feed their habit. Many men ended up homeless doing nothing but smoking opium.

Opium () contributed significantly to the general trade in Singapore’s pioneering years. Encouraged by the British colonial government, it reaped great profit from opium licenses. However, many Chinese coolies succumbed to this vice as an escape from their harsh realities. Despite attempts to control and ban this narcotic and addictive drug, the opium trade continued clandestinely. The death penalty was introduced for opium drug dealers and peddlers in 1989 in a bid to put a complete stop to it.Opium smoking was an accepted social practice, by both the elite and poor, in 19th century China. The act of offering an opium pipe to a visitor was akin to serving tea. At the turn of the 20th century, opium addiction was still widespread among the Chinese. Based on the Opium Farmers returns, the sales ofin Singapore peaked at 1,639,873 tahils in 1903.Individuals and institutions initiated anti-opium movements to oppose opium trade and opium smoking. In 1907, an Opium Commission was appointed to assess the extent of opium smoking and set up measures to end it. The toxicity of opium smoking anddross were documented. It was reported that out of the 12,560 hospital admissions in Singapore from March 1907 to February 1908, some 1,626 were opium smokers. The February 1909 report found that there was no increased prevalence of the opium habit or increased evils arising from the use of opium in the past 10 years. Nevertheless, the Opium Commission recommended to abolish the present system of farming the opium revenue, implement a ban on opium sale to women and children under 18, and to suppress the use of opium in brothels.The Chandu Revenue Ordinance was enacted in 1909 followed by the creation of the Monopolies Department. The sale of opium became controlled and in 1925, the government issued licences to opium smokers to smoke opium in their own premises. In January 1929, supplies of opium were rationed and registration of opium smokers became compulsory and only adult Chinese above 21 were permitted to consume opium. In 1933, the Chandu Revenue Ordinance was amended and opium possession by those under the age of 21 was banned. In 1934, opium possession was banned by anyone who did not have a medical practitioner's certification that they needed opium for health reasons. However, there were still supposedly 16,552 opium addicts in 1941. During the Japanese Occupation (1942‒45), it is thought that the number of opium addicts could have risen to a high of 30,000.