Trades and trade-offs are implicit in modern air travel. Flights for miles. Miles for dollars. Dollars for extra anything. Tradeoffs in service for price. It’s a sub-culture of its own, but we travelers get it.

Until you head out on a family vacation, boarding a plane without seats next to your kids. Then the system breaks down. Then the culture turns medieval.

I’ve been on both sides of the aisle. When first class was part of my employee benefits “back in the day,” I thought the front of the plane should be a restricted area for those 18 and over. I mean, they’re serving champagne, and everyone is either a socialite or MBA – it’s no place for children!

But those days are over. They’ve just closed the gate behind me as I do the walk of shame, panting and sweating, down the center aisle on a Southwest 737. Made it! I’m barefoot, since I ran from TSA to the gate with my wedge heels still in one of my two massive tote bags, all 40 pounds of which are slung behind my shoulder pulling my bra strap down and my shirt with it. My three kids are behind me with their wheelies. At least I think they are, because I haven’t checked since they closed the gate.

Now the moment of truth. I’m on an unassigned seat carrier. There are no two seats together. Only middle seats and a few lone aisle seats left, and everyone has claimed territory for their belongings and settled in. It’s Milwaukee, so the passengers aren’t the puniest pumpkins in the patch either.

And I’m absolutely not asking someone in an aisle seat to move to a middle so that I can sit next to my daughter. I’m just not. I was late to the airport. Even if it wasn’t my fault that there was traffic and that I made three stops to drop off a playdate, pickup my kid’s sandals, and Snapchat a goodbye to the Midwest (it makes no sense, but I’m trying to be relevant to my post-millennial spawn). OK so it was my fault.

Now instead of begging, I execute my plan. I don’t cast a forlorn gaze across the remaining seats, and I don’t ask a flight attendant if there are any seats together – that’s freaking obvious. I tell my teenage boys: go take a middle seat, and tell my 9-year old: sit here in this aisle seat. With the aisle move I have gained a valuable trading chip. I look back two rows to the first free middle seat, and ask the guy in the aisle next to it to trade with my daughter’s aisle seat. Done. Aisle to aisle, fair and square, and we get two seats together.

Frantic families don’t end up in this situation just because they’re late to the airport. Seats get screwed up for lots of reasons. Airlines swap the type of aircraft on the route at the last minute, and your seat assignment goes out the window. You book the last few seats and are notified that the seat assignment will be made at the gate. Your flight is cancelled, and you are re-booked and thrown to the wolves.

Seat strategies aren’t just for one of these coerced conundrums on an unassigned seat carrier. You can reserve ahead strategically too. Want an empty seat next between two of you? Reserve the aisle and the window. That orphaned middle seat will be the last to go, and may end up empty (if it doesn’t, your unwanted middle passenger will be happy to swap for the window).

Same strategy for the open seating carriers: grab seats as far forward as possible. People keep heading back, hoping for an aisle, and give up and take a middle seat at the end – they rarely u-turn back to the front the get that same middle seat.

And if you’re reserving online, struggling with that seating map because there are no seats together, just reserve aisles in different rows. Aisle seats are your bargaining chips. Upon boarding, you can trade that aisle for an aisle or a middle, but you can only trade a middle for a middle, unless you want to beg, borrow, or steal.