Per Hokstad is senior research scientist at SINTEF Safety Research, and has thorough experience in research and projects on reliability and risk analyses; e.g. in transportation, oil/gas and water supply. Until 1985 he was Assistant/Associate Professor at NTH in probability, statistics and reliability, and he was also Adjunct Professor in risk at NTNU 1990-2000.Ingrid B. Utne is a Professor of marine operation and maintenance at Department of Marine Technology, NTNU. She has a PhD in safety and reliability, and she has worked on several research and industrial projects on risk analysis and maintenance management in shipping, oil/gas, and fisheries and aquaculture.Jørn Vatn is a Professor in maintenance optimization at Department of Production and Quality Engineering, NTNU. He covers the field of risk analysis, reliability analysis and maintenance optimization. Application areas are transportation, offshore oil & gas, offshore wind energy and utility services.