For a party to join the Comintern, it had to accept 21 conditions. Some of these were:
- To actively campaign in favor of communist ideas, both in the cities and the countryside
- To remove reformists and centrists from positions in the working class movement
- To combine legal and illegal methods of struggle, in countries with prohibitive anti-socialist laws
- To supervise the activities of any members in parliament
- To denounce excessive pacifism and accept that violent struggle is sometimes necessary
- To support liberation movements in the colonies
- To ensure their affiliated trade unions join the 'red' trade union international rather than the 'yellow' Amsterdam one.
- To organise on the basis of democratic centralism
- To support all existing Soviet republics
- To revise its party program by including the general policies of the International
- To accept all decisions of the Comintern as binding
- To expel all members who voted against any of the 21 conditions (or, if the majority of their party voted against them, to resign and form a new party)
- To take the name 'Communist Party'
