Virtually all English Grammar textbooks are written by native speakers of English. The way native and non-native speakers learn a foreign language in general and grammar in particular is diametrically natives learn subconsciously, whereas non-natives learn consciously.What makes this book different is that it's written by a non-native speaker of English from the viewpoint of someone who has deliberately studied English grammar and is very much aware of how non-natives perceive and produce grammar.Although this book is sold as a standalone textbook, it is best used as supplementary material to the author's first book VIRTUALLY NATIVE.
To be honest, I already had grammar books when I bought this one. I wanted to support Vladimir Skenderoff's work because I find the first book, Virtually Native very inspiring. It was a good choice because I like this grammar book! It is very clear with a lot of examples!
This is a concise book with the rules that we need to master to speak English decently. I think that it is even good to read this book several times and to start with this kind of book. Of course, we could also use other advanced grammar books of 400 pages that are often very expensive and more exhaustive but I think that it is not the best to start with. It is better to start with a book like English Grammar and Functions: by a non-native, for the non-native.