This presentation shows how many notorious space disasters were not due to inherent hazards of space, but were due to violating well-known principles of hi-tech safety. It provides explanations for the Challenger and Columbia shuttle catastrophes and for the 1999 Mars robot fleet disaster. Why did they happen when they were in hindsight avoidable? Safety cultures decay from causes such as lulling of anxiety through success; self-hypnosis based on superstitious statistical myths; loss of respect (fear) for past experience, and from elevation of other measures of goodness higher than safety. There is a discussion of the role of the Shuttle-Mir program in 1990’s in corrupting US space team’s attitude toward safety by elevating White House demands for diplomatic value above classic NASA safety standards. Once a series of predictable near-fatal disasters occurred, NASA leadership came to believe that because they had ‘gotten away with carelessness’ those times, they could count on the same happy results indefinitely. The key safety principle – prove an operation is safe, don’t assume it’s safe and expect skeptics to prove it’s NOT – was violated again and again by NASA, with lamentable and predictable results. In conclusion, although spaceflight will remain inherently dangerous, and although human nature allows additional dangers to be introduced unintentionally, appropriate attitudes can reduce -- but never eliminate – risk. Lastly, all technological risk is ‘related’ -- and lessons from space accidents (and avoidances) can dramatically drive home lessons for hazardous operations back on Earth.