The phrase “challenging behaviour” was invented nearly 40 years ago, in 1987, in a King’s Fund Centre report. Only two editors were named. The true authors were never made public. No disabled voices were credited. And yet this "UK-made phrase", never recognized in the DSM or ICD was adopted into policy, training, and guidance worldwide. Over time, it became a label pinned on children and adults. A tool to stigmatize. A justification for restraint, seclusion, and exclusion. So the question isn’t just where did this phrase come from? It’s: 👉 Who created it? 👉 Who benefited from it? 👉 And why has it been allowed to shape decades of harm? Since 2019, ICARS has been uncovering this history — mapping the UK entities, individuals, and networks behind the spread of this language, recovering out-of-print reports, analysing historic restraint training and ‘reduction’ manuals, and tracing how it shaped today’s culture of restraint and seclusion in education. Our research shows how a phrase with no science behind it, no collaboration with the disability community, and no disabled expertise has become embedded in policy and practice — propping up the very systems tied to the Restraint Industrial Complex. #AgainstRestraint