Nobel laureate Amartya Sen is renowned for his 'entitlement approach' to poverty and famine. He argued that starvation and poverty are not merely due to a lack of food or resources but rather due to people's lack of 'entitlement' – the ability to access food and other necessities through production, trade, labour, or transfers. He demonstrated how changes in entitlements can lead to famine even when overall food availability doesn't significantly decrease.