Foreword------------------------------------- SGML is misunderstood and underestimated. I have always wanted to write this book. I am pleased that two people with whom I have had the pleasure to work were finally able to do so. Since I have always been a bit of an evangelist, I feel pride when my "students" become recognized "teachers". In the early years of SGML we struggled to define a language that would bring the information to its rightful place. We succeeded. Then we had to explain these idea to technical adoptors. Again, I think we have succeeded. We have learned much about SGML in the process of implementing it. These