The first was held in Ottawa, Illinois (all the locations were in the state of Illinois), on August 21, 1858. Douglas led off that day; Lincoln had his one-and-a-half-hour rejoinder; and Douglas then concluded with his half-hour response.

The second debate was held at Freeport on August 27, 1858. This time it was Lincoln who opened, Douglas who made his rejoinder, and Lincoln who concluded with a half-hour response. The third debate was at Jonesboro on September 15, and this time Douglas opened. The fourth debate was at Charleston on September 18, and Lincoln opened. The fifth debate was at Galesburg on October 7; the sixth was at Quincy on October 13; and the seventh and final debate was held at Alton, on October 15, 1858.