From the reviews:
"This book treats measures which are invariant under group actions … . great care is given to make the book easily accessible to readers from a great variety of different backgrounds in keeping the mathematical prerequisites to a minimum and by making the exposition essentially self-contained. For a better understanding basic definitions and theorems are always illustrated by simple examples familiar from calculus." (Werner Strauß, Zentralblatt MATH, Vol. 1065, 2005)