This single arm, post-authorisation study is designed to evaluate the long-term safety of pirfenidone in participants with IPF. The enrolment of participants will be completed within approximately 24 months. Participants will receive pirfenidone according to the physician discretion and will be followed for 2 years. Treating physicians will collect pre-specified data at the baseline and every 3 months thereafter, for the duration of the participants' participation in study.