Humanity faces challenges related to the ecological crisis. It is essential to reformulate the development and use of technological innovations, as well as their social meaning and environmental impact. Recently, grassroots movements and bottomup initiatives have promoted alternatives to conventional approaches to innovation. This has caught the attention of academics, professionals, and local communities and coined relevant approaches such as frugal innovation and Low-Tech. However, there are still blurred conceptual and theoretical boundaries between these two approaches. This article studies Low-Tech and Frugal Innovation for their potential to promote sustainability. Through a review of the literature, key principles and criteria were identified. Two cases were studied for an empirical comparison of their similarities and differences. This study aims to contribute to the positioning of frugal innovation and the Low-Tech in the mirror of public discourse about innovation. This article also seeks to spread and continue the debate on the potential of bottom-up approaches towards sustainability.