Clostridium perfringens is one of the most widespread anaerobic spore forming bacteria found in the environment. The toxotype A of the species inhabits the gastrointestinal tract of birds and mammals exhibiting pathogenic properties in the immunocompromised host. The virulence determinants of C. perfringens are toxins and extracellular enzymes which cause gas gangrene, enteritis necroticans, food poisoning, and non-food borne gastrointestinal infections in humans. The young animals suffer from enterotoxaemia, dysentery and necrotic enteritis due to the anaerobic spore forming bacilli. This article reviews the epidemiological significance of C. perfringens and its disease diagnostics, taking into account all known to date virulence determinants of the microorganism.