Maasik’s book provides a quick, efficient read on how to get started with OKRs.
Following his previous book this offers an advanced guide on how to implement OKRs.
John Doerr’s book is a good intro from the grandfather of OKRs, looking at many first person, behind the scenes case studies. This is to demonstrate all the benefits that OKRs have created in so many organizations. The book is a self-help guide to raise the next generation of leaders.
Radical Focus: Achieving Your Most Important Goals with Objectives and Key Results by Christina Wodtke
Radical Focus is a nice, quick read in the form of a fable with some follow-up suggestions. Follow the internal struggle of 2 founders of a coffee connecting start-up and easily apply the lessons to your own goal making process.
Objectives and Key Results: Driving Focus, Alignment, and Engagement with OKRs by Paul R. Niven and Ben Lamorte
Lamorte and Niven’s book is the most in-depth and theoretical of these references. It serves as a reference guide more than anything written by two leading OKRs consultants and researchers.
You can discover other helpful OKR e-books here.