We did the baby swap when we were at WDW last week and it worked really well, especially if you have other children who would get to ride a second time with the "waiting" adult. All the biggies give out a special "swap" pass much like a fast pass (Space, Splash, BTMR, Mission Space, Fast track, RnR and ToT, Dinosaur). Both adults and baby have to "check in" with the first CM to get the "swap" pass (guess they had people abusing the system so almost every CM had to see me, my husband and baby together before they would give us the pass). As stated above, one adult then rides alone or with others in the party; the second adult waits at the end of the ride (none of the above attractions would let all of us go thru together) or at a special designated spot (Kali Rapids). Once the first adult is done, the second adult (and 2 additional riders) go thru the fast pass line to ride. My older kids LOVED it as they got to double the times they rode the "cool" rides without having to wait in long line, and it was nice that the adult "left behind" had someone to ride with each time. FYI: the Safari at AK and Buzz Lightyear did not have baby swap options.