This paper analyzes the extent of agency discretion under different assumptions concerning judicial review: a) discrete judicial decision making; b) multi-member courts; c) decision costs at the Courts; d) multi-layer judiciary. The main results of this paper are: a) discrete judicial decision making and decision making costs at the Court generate agency discretion; b) Agency discretion is reduced, however, by introducing further levels of judicial review; c) Multi-member Courts do not seem to generate important implications for agency discretion.