Testing inflation has become one of the main goals in observational cosmology, and one of the scientific priorities for the new generation of Cosmic Microwave Background projects. A race to more sensitive focal planes, combined to a high control of the instrumental and astrophysical systematic effects, is at play across the globe. In this talk, I will review some of the current and future observational efforts which are all aiming at detecting the inflationary, primordial gravitational waves. I will provide more details on one of them: the Simons Observatory, which will achieve its first light in 2021. I will finally illustrate some of the current challenge that the scientific community has to face, and its plans to overcome them.