The Mythical Man-Month
I am currently reading The Mythical Man-Month from Fred Brooks. This book consists of essays on software engineer. These essays draw from his experience as project manager for the IBM System/360 computer family and then OS/360, its massive software system.
I suggest read this book if you take part in any software project. I believe you will find parts similar to your own projects and learn from Brooks' experience.
For example, when a task cannot be partitioned because of sequential constraints, the application of more effort has no effect on the schedule. However, project managers sometimes try to shorten the schedule by assigning men. The following phase from the book perfectly explains the situation. 
The bearing of a child takes nine months, no matter how many women are assigned.