Jeff Cooper is the known as the founder of a great deal of modern pistol technique. His training Academy, Gunsite, is the longest running civilian training academy, and is still a successful training destination in Arizona.
This book, originally published in 1958 is a snapshot of the history of gunfighting and the old technique. I seriously considered not writing up this book simply due to some of the content being outdated. But looked at for what it is, a historic reference of what was believed over 60 years ago, it is an engaging book.
The good:
This book does have a great history of the fighting handgun. It begins with the flint and cap single shots and progresses through America in the 1800s. When it gets into the modern firearm, it is not limited by information, only the realities of the time. Cooper aspouses that the 45ACP M1911 is the only real choice for a true defensive handgun. At first look, this seems absurd to us. But looking at the available firearms, the types of available ammunition (practice "ball" or cast lead only), he may have it dead on the nose. His guidelines for holsters are good, saying it must be fast, secure and comfortable, as well as concealable if it applies. But some of the pictures of the holsters made in those years (they don't cover the trigger) are no what we demand today. It is also a good look into the origins of techniques such as the two handed grip, tactical reload, and point shooting, though some of these techniques have given way to better modern ones.
The not-so-good:
Like I said before, the ammunition and caliber debate is alive today because all of the ammo is so good. This book takes a 1958 view of what is acceptable, but it doesn't apply to your needs in 2021. His view on shot placement, though better than just the whole silhouette, is not what today's marksman and training professionals would call good or even acceptable. His view on double action pistols and revolvers is a professionals approach, but modern DA guns are a far cry for the ones of the 1950s. The DA revolver served faithfully for law enforcement until the 1980s or 90s and was a reliable and quality part of the arsenal in the hands of those that worked at it. Finally, the use of force and flippant talk of killing is somewhat outdated. In the 1950s, I imagine that having a good reputation went a long way in a courtroom. With evidentiary standards changing in the years past, as well as the media, I would generally dissuade someone from taking Coopers advice on likely legal outcomes.
All in all, when used as a history and origins book, this one is a good read. It is a good way to test what you believe to be true today off of the skill and knowledge of the past. Some is old, some stands up, and some we may just need to get back to the old ways.