Do not let the breathless predictions and gimmick-laden pilot tests by large tech companies fool you: drone deliveries are still a ways off.

We wrote in March that drone delivery will be a long time coming. And even though federal rules released since then allow the use of drones for commercial activities, there are major restrictions—including the fact that drones can’t fly above people or out of the line of sight of an operator without a waiver.

Even if regulations soften, there are still major hurdles to overcome before drone deliveries become regular occurrences. Among them are security, airspace management, and reliability, not to mention the small problem of what an aircraft does when it arrives at your home.

And yet suggestions of delivery drone applications keep coming. Alphabet is hauling Chipotle burritos across the campus of Virginia Tech aboard its Project Wing aircraft. UPS is testing a drone to send medical supplies. Mercedes-Benz has collaborated with drone-maker Matternet to design a vehicle that works as a mobile delivery hub.

The idea makes some sense: networks of delivery drones could provide swift and efficient shipping, reduce road congestion, and even help cut emissions.

But even keen proponents of the concept can be forced to admit that we’re in for a wait. In an interview with the Wall Street Journal, Andreas Raptopoulos, the chief executive of Matternet, said that airborne package delivery will reach an “inflection point around 2020.”

The same article also suggests that collision-avoidance standards being developed by the Federal Aviation Administration, which will be vital for an effective drone delivery network to take to the skies, will take “three or four years” to draft. According to the newspaper, that system will make use of sensors being developed by the Radio Technical Commission for Aeronautics. But work on those will conclude “sometime in 2020.”

All signs point to one conclusion: for now, you should select the drone delivery option only if you can tolerate an awfully long wait.

(Read more: Wall Street Journal, “Sorry, Shoppers: Delivery Drones Might Not Fly for a While,” “Now You Can Finally Use Your Drone to Make Money,” “Drones Get Set to Piggyback on Delivery Vans,” “Burrito-Delivering Drones—Seriously?”)