How many movies have Mamoru Oshii and Shuichi Hirata collaborated on?

They have worked on 4 movies together! Their first movie together was Patlabor: The Movie (1989) while their highest rated movie together was Jin-Roh: The Wolf Brigade (1999). They have not worked together since Ghost in the Shell 2: Innocence (2004). They are most known for their science fiction films together.