The threat from air pollution to Delhi is serious and now it is affecting our lives. But Delhi was the first place to adopt CNG as the fuel replacing diesel for all public transport and yet the air quality has deteriorated over the years. So what went wrong? Is there a serious threat to our well-being? Are trucks coming from outside and emitting poisonous air the main source of pollution? Should the Delhi government implement National Green Tribunal's decision? Why hasn't successive governments planned a bypass for trucks and vehicles to avoid the city? Should there be a curb on diesel cars? A debate on The Big Fight.