This classic review outlines several therapeutic uses of carbon monoxide (CO). The overall language of the report is very easy to understand and read while presenting in-depth descriptions and examples when needed. This review touches on the primary pathways for endogenous production of carbon monoxide in mamals. It highlights the known biological roles of CO and describes some of the reported therapeutic implications. The review also focuses on various CO-donating systems and how they have been employed in the literature. Most importantly, this review clearly describes possible cellular targets of carbon monoxide and, in my opinion, highlights most of the known key cellular targets. Overall, this is a very good review to start learning about the physiological roles and potential therapeutic applications of carbon monoxide. I also have found most of its references to be high quality and provide ample support for the ideas and conclusions.