Microbially influenced corrosion (MIC) has been focusing increasing attention from different research areas in the last years, as an answer to the demand of wide variety of industries and degradation cases. The difficulty in reaching an adequate understanding of corrosion processes induced by microorganisms has result in cross-fertilization of ideas between researchers from different disciplines like microbiology, electrochemistry, metallurgy and materials engineering. Different MIC mechanisms can be simultaneously or alternately occuring on various materials, where a complex boundary layer of corrosion products, bacterial cells and other environmental factors are present on the surface. The paper discusses new aspects of MIC mechanisms induced by sulphate reducing bacteria species, taking into consideration modern techniques and new approaches in the study. Practical cases concerning microbial risks, failures illustrate the complexity of this phenomena: from local corrosion problems through stress corrosion cracking and hydrogen damage. The role of microstructure and chemical composition of materials is also highlited as a key factor in microbial damaging. In addition to this, the principal morphologies of attack and cracking are described.