All good things must come to an end — including your beloved ad-free Instagram.

In less than a year, Facebook’s billion dollar acquisition will be turning itself into a viable ad platform, Instagram director of business operations Emily White told The Wall Street Journal.

The move is perhaps a bit overdue for two-year-old Instagram, which is under pressure to show Facebook that it’s good for more than just photo filters.

But Instagram’s challenge is twofold: Not only must it create a valuable place for brands to advertise, but it also has to make sure the needs of the brands don’t outweigh the needs of the userbase, which has officially passed the 150 million threshold. (If you’re keeping count at home, that’s 20 million new users since June.)

Instagram knows firsthand what happens when its users react negatively to its decisions. When the company made some questionable changes to its privacy policy late last year, the most indignant of its users said they would stop using the service — and some of them did just that.

Instagram, for obvious reasons, wants to avoid a similar situation in the future, so it’s a good sign that White and her team are taking the ad push so slowly.

The last question is perhaps the most important: What will Instagram’s ads look like? While it’s not tough to envision something as simple as company-branded photos in the Instagram photo feed (a la Tumblr), Instagram is also exploring ways to allow brands to advertise via the app’s search function and Discover feature.

Regardless of what the ads look like, though, I think it’s safe to say they won’t be well received.