He created a commission to investigate hundreds of uncompleted contracts, already paid for. He enlisted the help of governments from United States to Switzerland to help recover billions of dollars stolen by corrupt officials. He also sent signals to the nation's military and police that corruption and strong-arm tactics would no longer be tolerated. It had an immediate effect. Nigerians say the police are less hostile and less likely to stop them and demand bribes.
Citizens also feel more freedom to express themselves.
In Abacha's time, we wouldn't be able to stand here and talk like this. Even some small things have changed. When Abacha traveled to the airport in Abuja, security police shut down traffic on the airport highway for several hours. All flights would be delayed. Obasanjo travels in a smaller entourage, and the police do not block the roads for the presidential motorcade.