With the introduction of Apple's Siri and similar voice search services from Google and Microsoft, it is natural to wonder why it has taken so long for voice recognition technology to advance to this level. Also, we wonder, when can we expect to hear a more human-level performance? In 1976, one of the authors (Reddy) wrote a comprehensive review of the state of the art of voice recognition at that time. A non-expert in the field may benefit from reading the original article.34 Here, we provide our collective historical perspective on the advances in the field of speech recognition. Given the space limitations, this article will not attempt a comprehensive technical review, but limit the scope to discussing the missing science of speech recognition 40 years ago and what advances seem to have contributed to overcoming some of the most thorny problems.