The world’s first commercial drone delivery service is in Rwanda, and it’s delivering blood.

The service is operated by Zipline, a US robotics and drone company. The drones drop blood parcels on parachutes outside remote health centers. Rwanda’s government pays Zipline for the deliveries, each of which costs about the same as the motorbike deliveries used previously, according to Keller Rinaudo, Zipline’s CEO. (The company declined to say how much that was, saying it would defer to the government to release the figure.)

Health workers can request a blood drop via text message, and it arrives around 30 minutes later. That makes a big difference in a country where short road trips can take hours. Blood loss after birth is one of the reasons maternal mortality is much higher in poor countries than rich ones; it’s the leading cause of death in Rwanda for pregnant women. And blood has to be stored carefully and matched to the recipient.

This is a video of the first blood delivery, from Zipline:

For now, Zipline will make between 50 and 150 deliveries per day to 21 clinics in the western half of the country. UPS, the US delivery and logistics giant, helped ship all of Zipline’s equipment to Rwanda. The UPS Foundation, the company’s charitable branch, earlier this year invested $1.1 million in a project to investigate how such drone delivery could be expanded to other medicines, and other countries.

And while for now the Rwanda service will just deliver blood, there are plans to expand into other medical areas, such as vaccines. Gavi, a public-private partnership which promotes vaccination, is partnering with UPS and Zipline on the research.

But while drones are being hailed as a solution to many problems across Africa, ranging from HIV testing to elephant conservation, they aren’t a simple business. Rwanda’s regulators are treating them favorably, but those in many countries don’t.

Kenya, worried about terror threats, banned commercial drones in January 2015. Ghana wants all drones registered and licensed, and is threatening hefty prison terms for anyone who doesn’t follow the guidelines. Nigeria has sought to cash in by making such licenses prohibitively expensive. South Africa, meanwhile, appears more lenient, though perhaps not so commercially savvy as Rwanda: it allows anyone over 18 to fly a drone for fun, but using one for business purposes requires onerous paperwork.