Fungi are at the forefront of many world issues: soil health and fertility, plant productivity, waste decomposition and treatment, biodeterioration, bioremediation, and biofuel production among others. Their activities directly influence ecosystem function and human well-being in multiple positive and negative contexts. Therefore, understanding their biology and the way they interact in natural and synthetic habitats is paramount in order to fully understand their roles and functions, and how such findings can inform new tools and biotechnologies to benefit mankind. Fungal Interactions is an open access international journal that publishes high-quality peer reviewed research papers covering a range of scientific areas where interactions between fungi and any biotic or abiotic factors occur. We are looking for contributions that highlight the importance of any fungal species in these interactions and that which contribute fundamental or applied knowledge to this research area. Areas of interactions covered by this journal will include, but are not limited to, fungal interactions with other fungi, microorganisms (e.g. bacteria, archaea, cyanobacteria), viruses, algae, plants, and animals (including arthropods, insects, humans and other mammals), as well as in aquatic and terrestrial natural and synthetic habitats, responses to environmental perturbations, e.g. climate change, stress responses, organic and inorganic pollutants, and involvement in element transformations and nutrient cycling. As a multidisciplinary journal we aim to publish papers that span a large number of research areas and at different research scales from molecular (e.g. molecular communication and sensing, biosynthesis and biological activity of secondary metabolites, genome evolution) up to ecological interactions (global shifts of fungal plant pathogens, lichens, mycorrhizas, biocontrol). By publishing research about these interactions in a single high-quality journal, we aim not only to create a forum for fundamental research but also for the development and discussion of new fungal-based biotechnological, agricultural and applied solutions that will contribute to solving the great challenges that mankind will be facing in the coming years.