I found this to be a very useful expansion to the Tomorrow's War rules.
The book provides a short history on alien contact in the Tomorrow's War universe, which describes mankinds encounters with the three non-human species.
The next section provides a brief overview and some details on non-human biology and psychology, and their game effects, furthermore it looks at humanity through the xenopsychology microscope as well highlighting mankinds defining psychological qualities for game purposes.
Next is a section on special operations forces which discusses the unaugmented operator, power armoured operator, nanite and genetically enhanced operators, cyborg and synthetic operators and hybrid operators.
Having discussed non-humans and special operations forces, the next section moves on to detail the specific traits that make them different and how they apply in game, expanding on the limited descriptions contained in TW.
With their traits described, the book then provides a section on sample forces such as the Dhargaur, Dhargaur Slave Races, Marshborn, DPRG Victoriuos People's Guard (Powered Armor SOF), DPRG Special Reconnaissance
Platoon (Cyborg Special Operations), 1er Régiment de Forces Spéciales Améliorées (Les Marteaux de Dieu), Republic of Arden National Guard Special Operations Force (RANGSOF), US Army Detachment Zulu (Genies), US Army Special Operational Detachments (Paragons), USMC Force Special Operations Command (Nannies).
These forces need special vehicles and weapons, which the next two sections details.
Finally the book provides over half a dozen scenarios involving these new forces.
Even if you use a different set of rules this book is worth buying as a game resource.