Anyone who has ever experienced a Virtual Reality (VR) environment has dreamed of being able to touch the virtual objects and manipulate them with his or her bare hands. Sadly, that requires much more than just a fast graphic board and an immersive visual display. For multi-finger interaction, this requires some kind of wearable force-feedback device, a so-called ‘haptic glove’. The recent growth of the Virtual Reality market resulted in an intensification of development efforts in this technology. These days many teams and start-ups around the world are announcing imminent releases of commercial haptic gloves. Indeed, in the last year there has been one new product announcement almost every month. It is clear that not all new ideas will actually make it to the market, and that not all haptic gloves are addressing the same range of applications. In this paper, the main technical constraints which are faced when designing a haptic glove are addressed with a special focus of the actuation technology. Then, a review of existing devices, past and present projects, comparing their characteristics and performance is provided. Lastly, insights on future developments are sketched.