As we enter a new decade filled with unpredictable beauty trends and an ever-expanding host of cosmetic offerings, one thing that seems certain to continue into the 2020s is the high price tag on so many procedures and products. With the cost of aesthetics increasing every year, the prospect of free filler or complimentary skin care can seem more tempting than ever. And one of the best ways to score a coveted treatment without paying its hefty fee is to participate in a clinical trial.

However, while clinical trials can seem like the ultimate win-win, whereby you commit to regular appointments over the course of a few weeks or months in exchange for a free procedure or product that would otherwise cost up to thousands of dollars, they’re not always so simple. In order to take part in trials, you must meet a long list of requirements, consider the various pros and cons, and potentially sign away your rights. Here’s what you should know if you’re curious about getting involved in one.