The book covers several memory improvement principles such as Interest, Selection, Attention, Understanding...(11 principles). Several memory systems are explained in the book : Observation, Concentration, Visualisation/Imaging.. (7 systems). The book also covers a system for remembering names and numbers. I thought the names section was quite good. I decided not to learn the number system, but as it says in the book, it is not for everybody. More...The book is not about complicated memory systems. Systems are explained very well and easy to understand. I recommend this book for anyone intending to improve their ability to remember.