The Japanese managed the economies of occupied territories primarily to benefit their war effort through systematic exploitation of resources. They redirected agricultural production to support their troops, commandeered industries for military manufacturing, and requisitioned raw materials. Economic policies were implemented to create a self-sufficient war economy, minimising reliance on external resources. Forced labour and conscription were used to meet labour demands. The Japanese introduced military currency to replace local currencies, which they used to purchase or requisition supplies, contributing to inflation and economic instability in the region.

The environmental impacts of the Japanese occupation in South-East Asia were significant, though often overlooked. Exploitative resource extraction, such as intensive mining and logging for war materials, led to environmental degradation. The construction of military infrastructure, most notoriously the Burma Railway, caused deforestation and altered landscapes. Additionally, the prioritisation of agriculture for Japanese needs disrupted local ecosystems and biodiversity. The occupation's focus on immediate resource extraction and agricultural output had detrimental long-term effects on the environment, contributing to ecological imbalance that took years to address post-occupation.

The Japanese occupation significantly altered the educational systems in South-East Asia, imposing a curriculum that focused on Japanese language, culture, and loyalty to the Emperor. Schools became tools for indoctrination, with an emphasis on military training and physical labour. Traditional subjects and local histories were sidelined or revised to fit Japanese perspectives. These changes aimed at creating a compliant and industrious population that would serve the occupational forces. After the occupation, these educational disruptions required substantial reform to re-establish local cultural identities and educational autonomy.

During their occupation, the Japanese often dismantled traditional local leadership structures to consolidate their control. In many areas, local rulers and aristocrats were stripped of their power and replaced by Japanese officials or local collaborators. However, in some cases, the Japanese co-opted traditional leaders to serve as intermediaries, exploiting their influence to administer indirect rule. This approach was part of Japan's broader strategy to maintain order while minimising resistance, but it frequently undermined the authority and legitimacy of these traditional structures, leaving a power vacuum after the war.

The Japanese occupation had a profound impact on ethnic relations in South-East Asia, often exacerbating existing tensions. The Japanese favoured certain ethnic groups over others, creating a hierarchy that placed Japanese nationals at the top, and this led to resentment among the local populations. For example, in Singapore and Malaya, the Chinese were specifically targeted during the Sook Ching massacre due to suspicions of anti-Japanese activities. Such policies deepened ethnic divides, which sometimes pitted communities against each other and had long-lasting effects on inter-ethnic relations in the region.