Recently, biochar has been the focus of increasing research attention. Reflecting this trend, a field experiment was set up to test the potential of biochar as a soil ameliorant in Slovakia in 2014. This is a collaborative effort, where local core teams from the Slovak University of Agriculture and the Slovak Academy of Sciences work together with international experts to elucidate the effects of biochar addition (Poland, Russia, Switzerland, Czech Republic and the UK). Since the start of the experiment, a number of interesting findings have been made and widely published. Both positive and negative impacts of biochar application on soil function and its ability to support crop production were found. Reduction of greenhouse gas (CO₂, N₂O) emissions from the soil into the atmosphere after biochar application was among the key foci of the experiment. In the future, research broadening the knowledge base on biochar use should focus on: (i) economically cost-effective biochar production and application within the Slovak Republic to different soil types, (ii) the nutrient content of biochar, both total content and available forms and their ratio, with the view of eliminating negative impacts of biochar on crop yields; (iii) different types of biochar and their combinations with other organic and/or mineral fertilizers and their repeated application, (iv) optimum biochar application rates to improve the sustainability of agricultural production.