IFYC's work is based on three guiding ideas that draw from relevant social science data and research: (See sources below)
1. Appreciative knowledge of diverse religious traditions and philosophical perspectives.
The amount of knowledge one has about a religion corresponds to positive attitudes toward that religion. Interfaith activities should create opportunities for participants to learn more about diverse perspectives.
2. Meaningful encounters between people of different faith and philosophical backgrounds.
Actually knowing someone of a particular faith positively impacts one's attitudes toward that religion overall. The power of interfaith activities comes from firsthand encounter which can transform negative stereotypes.
3. Common action projects between people of different backgrounds.
Relationships that involve common activities influence both personal attitudes and the bonds of a community. This is why IFYC advocates for interfaith cooperation, work such as service-learning and social action, that facilitates such meaningful encounters and builds social capital.
You can find an extended explanation of these ideas here.