One in a series of talks from the 2019 Models of Consciousness conference. Stuart Hameroff Center for Consciousness Studies, University of Arizona, Tucson, Arizona The Penrose-Hameroff ‘Orchestrated objective reduction’ (‘Orch OR’) theory suggests consciousness arises from ‘orchestrated’ quantum superpositioned oscillations in microtubules inside brain neurons. These evolve to reach threshold for Penrose ‘objective reduction’ (‘OR’) by E=h/t (E is the gravitational self-energy of the superposition/separation, h is the Planck-Dirac constant, and at the time at which Orch OR occurs) to give moments of conscious experience. Sequences, interference and resonance of entangled moments govern neurophysiology and provide our ‘stream’ of consciousness. Anesthetic gases selectively block consciousness, sparing non-conscious brain activities, binding by quantum coupling with aromatic amino acid rings inside brain proteins. Genomic, proteomic and optogenetic evidence indicate the microtubule protein tubulin as the site of anesthetic action. We (Craddock et al, Scientific Reports 7,9877, 2017) modelled couplings among all 86 aromatic amino acid rings in tubulin, and found a spectrum of terahertz (‘THz’) quantum oscillations including a common mode peak at 613 THz. Simulated presence of 8 different anesthetics each abolished the peak, and dampened the spectrum proportional to anesthetic potency. Non-anesthetic gases which bind in the same regions, but do not cause anesthesia, did not abolish or dampen the THz activity. Orch OR is better supported experimentally than any other theory of consciousness. Filmed at the Models of Consciousness conference, University of Oxford, September 2019. Creative Commons Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales; http://creativecommons.org/licenses/by-nc-sa/2.0/uk/