We purchased the Bumbo seat for my baby when he was just 6 weeks old. Obviously he didn't have the control to sit in it for long periods of time by himself. But we started with a few minutes at a time until he was holding his head up on his own. Once he got big enough to really sit in it by himself he LOVED it and would sit for what seemed like for ever and play and eat cheerios...we also had the tray that fits on it. I definitly attribute the Bumbo seat for helping him learn to sit up by himself. He was sitting un assisted by 5 months. Even now that he is 19 months he still likes to sit in it...