This first volume will cover the aircraft and operations of the reconnaissance units from their origins in clandestine survey and photographic work over Poland and the United Kingdom in the late 1930s through to their first operational use during the Spanish Civil War. When World War II began, Aufklarungsflieger were involved on every front where the Luftwaffe fought. They were active in the skies across Europe, from Poland in the east to Britain in the west. They also played their part in the invasions of the Balkans and Russia.