The imposition of Emergency in 1975 had a profound impact on the party system in India. It set off a process of significant change in the structure and functioning of political parties.

The most immediate effect was seen in the 1977 Lok Sabha elections, where Indian democracy came closest to looking like a two-party system. For the first time since Independence, the Opposition came into power at the Centre. The Congress party suffered a dramatic defeat, which was a direct consequence of the unpopularity of the Emergency.

The period after the Emergency witnessed major realignments in the party system. Soon after its defeat, the Indian National Congress split into two groups. Similarly, the Janata Party also went through major convulsions. These splits indicated that the party system was undergoing a fundamental transformation.

The elections after the Emergency marked the beginning of a change in the party system. The Congress, which had recovered after 1971, "was not the same kind of party" after the Emergency. The period can be described as one of both constitutional crisis and political crisis, which reshaped party politics in India fundamentally.