This work reflects preoccupations with the threats posed to our environment due to climatic factors, major and natural hazards of all kinds and demographic influences. Earth Observation from Space is a unique tool to observe these phenomena at relevant time and space scales. Research laboratories worldwide are striving to advance the science and develop the applications. Papers presented here seek to strike a balance between the theory and the applications. They are grouped according to themes, many related to natural hazards: land surface processes, ocean, ice, coastal zones, fires and mass land movements and atmospheric risks. European laboratories, together with colleagues from other continents, are rising to the challenge to monitor changes and to find solutions to protect and improve life on planet Earth.