This textbook provides graduate students with a thorough and up-to-date introduction to inflationary cosmology. Enormous progress has been made in this area in the last few years and this book is the first to provide a modern and unified overview. It covers all aspects of inflationary cosmology and carefully compares predictions with the latest observations, including those of the cosmic microwave background, the clustering and velocities of galaxies and the epoch of structure formation. Problems are included throughout to help the student to develop a thorough understanding. With the host of international experiments currently being performed and planned for the near future (including NASA's MAP satellite, and the European Space Agency's Planck mission), inflationary cosmology promises to be one of the most exciting and fruitful topics of research in science in the next decade. This book provides graduate students with the ideal introduction.