This article examines two modalities of law, depicted spatially as the vertical and the horizontal. The intellectual background for seeing law in vertical and horizontal dimensions is to be found in much socio-legal scholarship. These approaches have challenged the modernist, legal positivist and essentially vertical view of law as a system of imperatives emanating from a hierarchically superior source such as a sovereign. In keeping with the socio-legal critical tradition, but approaching it from the perspective of legal philosophy, my aim is to address three matters. First, why is vertical law problematic for feminists? Second, what are the theoretical characteristics of law in its horizontal register? Third, how is an appreciation of this 'flat' law useful for feminist legal theory and practice? In particular, I consider the ways in which feminist legal theory operating in the horizontal dimension can transgress, without transcending, the vertically determined perimeters of the nation state.