Today - 22nd May - we celebrate the “International Day for Biological Diversity” and soil biodiversity plays a pivotal role in the functioning of the Earth’s ecosystems. Soils are widely recognized as a major reservoir of global biodiversity and up to 90% of organisms in terrestrial ecosystems spend part of their life cycle in soil habitats. Besides improving soil conditions to grow healthy and nutritious food, soil biodiversity contributes to many other ecosystems services such as stabilization of greenhouse gases and control outbreak of plant, animal and human diseases. Soil biodiversity constitutes an important source of genetic resources for biotechnological and medical innovation. Yet, the loss of soil biodiversity is considered one of the major soil threats in many regions of the world. Despite the enormous scientific progress made to date, the protection and monitoring of soil resources at national and global levels face complex challenges, restricting the design and implementation of on-the-ground policies and actions.