The Reassess Your Chess Workbook: How to Master Chess Imbalances, by Jeremy Silman.
This is the workbook to Jeremy Silman's book "How to Reassess Your Chess: The Complete Chess Mastery Course".
Steven Winer writes at ChessCafe.com about "How to Reassess Your Chess: The Complete Chess Mastery Course":
"...one does not need How to Reassess Your Chess to use the Workbook, since the early chapters of the Workbook summarize Silman’s thinking techniques".
Link (pdf document) to what Steven Winer, at ChessCafe.com, has to say about the book The Reassess Your Chess Workbook: How to Master Chess Imbalances.
Silman books at Amazon:
The Workbook
How to Reassess Your Chess
The Amateur's Mind
Silman's Complete Endgame Course