I haven't read the other books in this series, but once you get into it then it works as a novel on its own.
Kal Skirata has been training clone troops, and comes to see them as his boys. They've started to have lives of their own, rather than just being mass produced copies of Jango Fett.
Kal wants to get them out of the army, and find a way to increase their built in limited life span. To this end, his troops have been hacking data from the Republic, building up a close unit of allies and siphoning money.
Palpatine has been building his own fleet of ships and getting his own clone army put into the action. When he sends out Order 66, telling them to kill all Jedi, its time for Skirata to try and get his troops somewhere safe.

Lots going on, sacrifices and bending the rules. Traviss writes good characters, making them more than a faceless representation of the Republic. An interesting read from the other sides point of view.

Der erste Roman zu Star Wars Republic Commando hört auf den Namen Feindkontakt und wurde von Karen Traviss geschrieben. Wieder einmal ist Literatur von einem Spiel inspiriert, auch wenn die Charaktere von RC hier nur erwähnt werden.

Ihr findet alle meine Rezensionen zuerst auf dichterdenkerchaoten.blogspot.de

The main problem with this book was length. Traviss apparently needed a better editor because this story could have been told with about 100 pages less. I wish I could rate it higher because I really wanted to like this book. The premise for a Star Wars novel is excellent: the point of view of the clones fighting for the Republic and the fall of the Republic as it gives way to the Empire all from the view of the minor characters, so to speak. The characterization in the book is pretty good as well. So for those reasons, I really wanted to like this book. However, Traviss just keeps spinning sidelines and adding more characters and details, and after a while, it just gets long. The event of Order 66 is pretty much the driving force; you know as a reader (especially if you are familiar with the events in the Star Wars universe) that the hammer is about to come down. Some suspense is good, but after a while, you can do so much stretching of your plot before a reader gets tired of waiting. After three quarters of the way into the book, I just scanned the rest to see who lived, who died, and how things turned out. Feeling that I had to scan is usually not a good sign. It tells me the author just tried to throw everything in, including the kitchen sink, then tried to wrap it all up in the end. Clocking in at a little over 400 pages was a bit much. The story was good, but it could have been a lot tighter and still pack the punch. As a couple other people have commented here, the author's ending was not exactly the most satisfactory (as others have pointed out, I won't say more to avoid spoilers), but I will leave that to the more hardcore SW readers to decide. As a casual reader of SW fiction, it was ok. I will add something else. If you have not read the previous novels in the Republic Commando series, you may miss a few things along the way. The characters have been developing during the series, and you may have a better appreciation of the characters if you have read the previous novels. I have not read the previous books prior to this one, which I picked up mostly out of curiosity. In spite of my reservations about Order 66, I am still considering picking up the previous works in the series because overall the idea behind the series is a good one. Also, I found very fascinating the descriptions of the Mandalorian culture (some of that could be a whole other book or novel by itself). This was a strength in the book for me.