In somewhat of a strategy reversal, Airbnb is once again giving selected third-party websites a chance to take a cut of its bookings by posting links to its roster of vacation- and apartment-rental properties.

This commission-generating business model, called affiliate marketing, means that many of Airbnb’s 4 million listings will become more broadly visible beyond the confines of the San Francisco-based company’s website and mobile app.

The advantage of affiliate marketing for a player such as Airbnb is that it would boost revenue while the disadvantages are that Airbnb would have to share that revenue with a third party, and these types of relationships come at the expense of promoting the Airbnb brand.

The revived Airbnb Affiliate Program is a return to formal relationships with third-parties websites. In late 2015, the home-sharing giant severely trimmed back its affiliate program to only a handful of partners, such as metasearch companies Hipmunk and GoEuro.

That older affiliate program likely didn’t generate enough bookings revenue, which probably led to the program’s demise.

Airbnb has now re-opened its affiliate program only to platforms that meet tough criteria — such as having one million or more monthly visitors. The more rigorous standards will likely lead to a greater upside than before for Airbnb.

Airbnb compensates the third-party websites for each booking and whenever new users sign up as hosts. It did not disclose compensation terms.

All About Airbnb was the first to report the revised affiliate program — and that deals site Groupon is one of the companies Airbnb is considering partnering with.

Other companies drive revenue through affiliate programs. Expedia Affiliate Network (EAN) is perhaps the most prominent, and one of the largest. That network, which is a significant part of the Expedia business, is aimed at small players as well as larger ones.

Airbnb’s version of affiliate marketing dovetails closely with metasearch.

Take its partner GoEuro as an example. If a customer goes to GoEuro to book a flight, bus, or train, they are likely to be offered a chance to search for a home share or vacation rental from Airbnb, too. A browser tab or window to Airbnb’s site may open by default, or the customer will be invited to click a link to visit the site.

If the customer ends up booking a property on Airbnb’s site, GoEuro will collect a commission. But the customer relationship and experience will remain controlled by Airbnb.

Other players might be eager to offer Airbnb inventory under the new program. It isn’t hard to imagine commercial relationships with metasearch brands like Kayak, Skyscanner, Google, Home2go, AllTheRooms, and Tripping.

In a separate move, Airbnb is now finally ready to give external software developers formal access to its search results via an API (application programming interface, or a method used for retrieving data). The external developers must meet its strict requirements for access, as noted by the All About Airbnb blog that first noticed the API.

It’s part of Airbnb’s broader outreach to the industry. On Monday, Airbnb co-founder and chief strategy officer Nathan Blecharczyk announced the debut of a new set of tools created for vacation rental property managers, some of whom manage hundreds or thousands of listings.

All About Airbnb also notes that Airbnb has created a widget that is embeddable on third-party websites to for event organizers.

Photo Credit: Airbnb hosts invite guests to stay in their rental on an island off of the coast of Portugal. Airbnb is seeking partnerships with large websites to further its sales strategy. Airbnb