HowTheLightGetsIn Festival is held every May in Hay-on-Wye, on the edge of the Black Mountains, alongside the picturesque River Wye. The world's leading thinkers debate ideas determined to get philosophy out of the academy and into people's lives. The festival also features a diverse programme of music, comedy acts, workshops, parties, and performances.

HowTheLightGetsIn Festival, hosted by the Institute of Art and Ideas, featured Ed Milliband, Noam Chomsky, Philip Pullman, Robert Skidelsky, Kimberle Crenshaw, Stanley Fish, and Steven Pinker. It attracts about 30,000 people each year. HowTheLightGetsIn Festival includes over 200 events, 80 debates and talks and 100 music and performance events.

The festival also debuted in London in September 2018 on the grounds of Kenwood House in Hampstead Heath. Since then, it's held in London every September.