Major changes that India had were due to disintegration of the USSR, India was forced to make structural changes on both the domestic and external fronts as our most trusted ally was disintegrated and our Economy was in very bad shape (gulf war was going on and license raj was at it's peak) and the Globalization was knocking our doors. So what we could have done when as per sources at that time we were considering to sell our gold to run the country. We went to the IMF and with some conditions, we had to open our economy which flooded our market with foreign brands, that is the reason we are fond of imported things because our Industry wasn't strong enough and the west was pumping it's goods into India at large.
Three major pointers to understand this:
Gujral doctrine - Shri IK Gujral gave 5 principle in which
He does not ask for reciprocity from our neighbors for the help.
No South Asia country should allow their territory to be use against India.
No interference in the Internal affairs.
Respect territorial integrity and the sovereignty.
Any dispute might arise should be solved through the peaceful and bilateral negotiations.
Manmohan doctrine -
Economic at the heart of the policies.
Greater integration with the world economy for the benefit of India.
India to work with International community to create global economic and security environment for all the nations.
More focus on regional institutional capacity and regional connectivity.
Modi Doctrine -
India first.
Engage the competing global powers, that is why we hear Quad grouping (USA, Australia, Japan and India), then increasing engagement with Israel, Arabs and the Saudi - Iran as well.
Lot of focus on the India diaspora, we have seen a lot of events he has conducted on foreign lands.
Modi government in the foreign policy is known for Panchamrit.
Samman - Dignity and honor in the global politics.
Samvad - Greater engagement and dialogue.
Samriddhi - Shared prosperity.
Suraksha - Regional and global security
Sanskriti evam Sabhyata - That is the cultural and civilizational linkages.