The formation of galaxies is one of the greatest puzzles in astronomy, the solution is shrouded in the depths of space and time, but has profound implications for the universe we observe today. This book discusses the beginnings of the process from cosmological observations and calculations. It examines the different theories of galaxy formation and shows where each theory either succeeds or fails in explaining what we actually observe. Coverage draws on the most recent observations of galaxies in the early universe, obtained by the very latest ground- and space-based telescopes. In addition, the book looks ahead to what we may expect to uncover about the epoch of galaxy formation from the new and upcoming generations of telescopes and technology.