I'm not sure if anyone else has commented on this but we had a devil of a time making our connecting flight at IST airport. We flew from Izmir to Istanbul and we were connecting to a flight to Toronto. We had 2 hours between flights so we thought that would be plenty of time. Our flight from Izmir left on time at 11:15 AM. Our Rick Steves guide warned us that because the airport in Istanbul was not yet complete there was additional time required to taxi the plane. The flight was about 40 minutes air time. The taxi to the drop off spot took about 15-20 minutes. We had to deplane to a bus to take us to customs which took more time. Then there was a really long line at customs. We were in line about 20-30 minutes. After customs there was another long line to get back into the airport which took another 15-20 minutes. Based on a sign in the airport we had an estimated 20 minute walk to our connecting gate. We sprinted to make it in 10 minutes. At the gate there were 3 consecutive security checkpoints to get into the gate area (I have no idea why). If we had not sprinted to our gate and if our plane had not been delayed we probably wouldn't have made our flight. Thankfully we did. Based on our experience I think you need at least 2 1/2 - 3 hours between flights to make sure that you make your connecting flight.