Peter Drucker 
The Practice of Management [PDF ebook] 

This classic volume achieves a remarkable width of appeal without sacrificing scientific accuracy or depth of analysis. It is a valuable contribution to the study of business efficiency which should be read by anyone wanting information about the developments and place of management, and it is as relevant today as when it was first written.
This is a practical book, written out of many years of experience in working with managements of small, medium and large corporations. It aims to be a management guide, enabling readers to examine their own work and performance, to diagnose their weaknesses and to improve their own effectiveness as well as the results of the enterprise they are responsible for.