If you're flying with strollers, you'll need to confirm with your airline in advance whether you have to check in your stroller with your baggage upon arrival or whether you can take it up to the gate.
If you are allowed to take it to the gate, it will then be placed in the plane at boarding time, and returned to you upon landing.
With some airlines this will depend on the size of the stroller, with only larger strollers being required to be checked in.
However, this is not always the case.
If you have to check in your stroller and if you will be changing planes, find out whether there will be strollers to borrow at your immediate destination, as this is sometimes an option.
However, even if strollers are generally available, you may arrive to find out that all the available strollers are out on loan.
the last flight I took to London with my 16 month old daughter to, I confirmed with the airline in advance what the check in arrangements were with strollers and was told they had to be checked in with the rest of my luggage.
I duly did this, but later, on arriving at the boarding gate, discovered numerous passengers who had been told they could keep their stroller until boarding and the stroller would be available when waiting for a connecting flight.
I, in contrast, traveling alone with my daughter had to carry her as necessary as we waited 4 hours for our connecting flight in Kuala Lumpur.
The upside if you do have to check in your stroller, and you have an active toddler, is that they will end up walking around the airport a lot more and, consequently, will (hopefully) sleep better once you board the plane!
Even if you are able to hand over your stroller at the gate, check when it will next be available. On my return flight to Melbourne, I handed the stroller in at the gate, but then had to wait for it to arrive on the carousel, having first passed through immigration (quite a walk) rather than having it given to me as I stepped off the plane.
Finally, if the stroller is checked in there is always the risk that it be damaged on a long haul flight, even if it is checked in with the fragile luggage. You might want to check what your insurance cover is if your stroller is damaged.
If possible, try and put the stroller in a bag, or at least strap it up as much as you can, in case it is loaded on and off the aircraft rather too roughly.
Flying with Strollers can help you in and out of the airport so long as you know what your limitations are.