Sovereign Wealth Fund (SWF) investors operate within the sphere of a variety of legal norms, including national laws, which in turn may be shaped or influenced by treaty obligations of their home and recipient states, and ‘soft law’ instruments. This article will examine the familiar issue of legal fragmentation of norms, in the evolving context of SWF activities. The issue is examined particularly from the perspective of their treatment in recipient countries, national security concerns that may arise from such investments, and recent ‘soft’ law developments. It compares recent legislative changes in a number of jurisdictions, their possible implications for SWFs, and whether there may be a place for sui generis rules to govern SWF investments. Relevant provisions from investment and trade agreements are also discussed.