A good read and still pretty applicable. There are more modern texts in the field, but few surpass its impact in the field. I would further recommend Principles of Modern Radar by Mark Richards or Modern Radar System Analysis by David K Barton as a more current and applicable text in the field.
I tend to rate 3 to 5 stars as I don’t bother with books that aren’t acceptable to the subject. 3 stars means it is a good book, but there are better treatments of the subject matter. 4 stars means the book is great and I use it regularly in projects/research. 5 stars is reserved for top 10-20% on a given shelf that abstracted a particularly difficult idea in an easy to understand manner (i.e. it blew my mind).
Each chapter is devoted to a specific aspect of radar design such as clutter, antennae, receivers, etc. The author presents some basic math but is not overly math intensive. The most surprising (and my favorite) thing about the book is that the author presents not only what works in radar design but also what has been tried and doesn't work.
This canonical text should be on the shelf of all radar engineers--as a reference. This is not an easy book to learn radar from. Grab one of Mahafza's books first, then go back to Skolnik for more detail.