Bacillus subtilis is a motile gram-positive bacterium widespread in the soil and the gut of animals which has been reported to cause opportunistic infections in immunocompromised patients. In Bacillus subtilis: Morphology, Functions and Role in Disease Management, the authors begin by outlining the main features of chemotaxis as a behaviour, then reviewing the molecular machinery Bacillus subtilis uses to sense and respond to chemical cues. Following this, the authors discuss how bacterial biofilms can form on biotic and abiotic surfaces, developing various reversible and irreversible stages depending on environmental conditions. An important characteristic of biofilm is the extracellular matrix, which is usually formed by exopolysaccharide and extracellular proteins by Bacillus subtilis. Next, this compilation highlights the key features in Bacillus subtilis lipopeptides as eco-friendly controllers of plant pathogens. Currently, phytopathogens impact all agricultural systems, leading to economic losses worldwide. The closing chapter discusses NKCP®, a novel dietary supplement derived from traditional Japanese traditional food, which improved patients’ symptoms and blood pressure by improving blood flow through antithrombotic and fibrinolytic properties.