At it's most basic level, this is a good introduction for Christians who haven't previously read anything about Islam or engaging Muslim people. Houssney truly loves Muslim people and desires to help them come to a living faith in the Messiah, and this comes through. Many of his practical suggestions for witness are also good introductions to this for many.
In my opinion, however, this book falters when Houssney makes blanket generalizations (e,g., serious essentializing concerning Arab peoples), or assertions vis-a-vis those with a more "contextual" approach. Altogether, I'd probably recommend Pastor Accad's classic, "Building Bridges" over this tome by his compatriot.